View source for Ido

{{short description|Constructed international auxiliary language}}
{{About|the language|other uses|Ido (disambiguation)}}
{{distinguish|Edo language}}
{{Use dmy dates|date=March 2021}}
{{Infobox language
| name             = Ido
| nativename       = ''Ido''
| image            = Flag of Ido (new).svg
| imagescale       = 0.7
| imagecaption     = 
| pronunciation    = {{IPA|io|ˈido|}}
| creator          = [[Delegation for the Adoption of an International Auxiliary Language]]
| created          = 1907
| setting          = [[International auxiliary language]]
| speakers         = 100–200
| speakers2        = 26 native speakers in [[Finland]] (2022)<ref name="StatFin"/>
| ref              = <ref name="Blanke"/>
| date             = 2000
| agency           = [[Uniono por la Linguo Internaciona Ido]]
| fam2             = [[International auxiliary language]]
| fam3             = [[Proto-Esperanto]]
| fam4             = [[Esperanto]]
|fam5              = [[Esperantido]]
| script           = [[Latin script]]
| posteriori       = based on the [[1894 Esperanto reform project]]
| iso1             = io
| iso2             = ido
| iso3             = ido
| lingua           = 51-AAB-db
| glotto           = idoo1234
| glottorefname    = Ido
| notice           = IPA
| familycolor      = 
}}
{{Ido sidebar}}

'''Ido''' ({{IPAc-en|ˈ|iː|d|oʊ}}<ref>{{Cite OED|Ido|access-date=30 September 2024}}</ref>) is a [[constructed language]] derived from [[Reformed Esperanto|a reformed version]] of [[Esperanto]], and designed similarly with the goal of being a [[international auxiliary language|universal second language]] for people of diverse languages. To function as an effective ''international auxiliary language'', Ido was designed specifically to be [[Grammar|grammatically]], [[Orthography|orthographically]], and [[Lexicon|lexicographically]] [[Regular inflection|regular]] (and, above all, easy to learn and use). It is the most successful of the many [[Esperanto]] derivatives, known as ''[[Esperantido]]j.''

Ido was created in 1907 due to a desire to reform the perceived flaws of Esperanto, a language that had been created 20 years earlier to facilitate international communication. The name comes from the Esperanto word ''{{Wikt-lang|eo|ido}}'', meaning "offspring",<ref>{{cite web
|title=Esperanto-English Dictionary
|url=http://esperanto-panorama.net/vortaro/eo-en-u.htm#I
|access-date=12 February 2012
|archive-date=22 February 2012
|archive-url=https://web.archive.org/web/20120222132607/http://www.esperanto-panorama.net/vortaro/eo-en-u.htm#I
|url-status=live
}}</ref> since the language is a derivative of Esperanto. After its inception, Ido was endorsed by some of the Esperanto community. A setback occurred with the sudden death in 1914 of one of its most influential proponents, [[Louis Couturat]]. In 1928, promoter [[Otto Jespersen]] quit the movement for his own language [[Novial]].

The popularity of Ido decreased for two reasons: the emergence of further schisms developing from competing reform projects, and a general lack of awareness of Ido as a candidate for an international language. It was not until the spread of the Internet that it began to regain popularity.

Ido uses the same 26 letters as the [[ISO basic Latin alphabet|English (Latin) alphabet]], with no [[diacritic]]s. It draws its vocabulary from English, French, German, Italian, Latin, Russian, Spanish and Portuguese, and is largely intelligible to those who have studied Esperanto.

Several works of literature have been translated into Ido,<ref>{{cite web
|title=Libreyo
|url=http://www.ido-vivo.info/
|language=io
|date=27 January 2018
|access-date=27 December 2018
|archive-date=3 January 2019
|archive-url=https://web.archive.org/web/20190103065824/http://www.ido-vivo.info/
|url-status=live
}}</ref> including ''[[The Little Prince]]'',<ref>{{cite book
|author=Antoine de Saint-Exupéry
|date=2013
|title=La Princeto
|url=https://drive.google.com/file/d/0BwBpiyu9JW2TV3RLTnNpWTM1dlU/view
|language=io
|translator=Fernando Tejón
|access-date=27 December 2018
|archive-date=26 October 2023
|archive-url=https://web.archive.org/web/20231026022557/https://accounts.google.com/v3/signin/identifier?continue=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F0BwBpiyu9JW2TV3RLTnNpWTM1dlU%2Fview&followup=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F0BwBpiyu9JW2TV3RLTnNpWTM1dlU%2Fview&ifkv=AVQVeyzYxCtGtfiMjlv7dVyR_ssSsxZI0AfO5BPo0mGPNH-tzKco0FHXlC3kM0bPl0qTMOYOLPXj1w&osid=1&passive=1209600&service=wise&flowName=GlifWebSignIn&flowEntry=ServiceLogin&dsh=S671368051%3A1698287157427945&theme=glif
|url-status=live
}}</ref> the Book of Psalms, and the [[Gospel of Luke]].<ref>{{cite web
|title=Evangelio da Santa Lukas
|url=http://www.ido-vivo.info/evangeliolukas.pdf
|language=io
|translator=L. Kauling
|date=1926
|access-date=27 December 2018
|archive-date=9 May 2018
|archive-url=https://web.archive.org/web/20180509022533/http://www.ido-vivo.info/evangeliolukas.pdf
|url-status=live
}}</ref> As of the year 2000, there were approximately 100–200 Ido speakers in the world.<ref name="Blanke">Blanke (2000), cited in Sabine Fiedler [https://books.google.com/books?id=CAIZ9BHOkBwC&pg=PA779 "Phraseology in planned languages"] {{Webarchive|url=https://web.archive.org/web/20230919120628/https://books.google.com/books?id=CAIZ9BHOkBwC&pg=PA779 |date=19 September 2023 }}, ''Phraseology / Phraseologie,'' Walter de Gruyter 2007. pp. 779.</ref> As of 2022, Ido has 26 speakers in [[Finland]], according to [[Statistics Finland]].<ref name="StatFin">{{Cite web |title=/ StatFin / Population structure / 11rm -- Language according to sex by municipality, 1990-2022|url=https://pxdata.stat.fi/PxWeb/pxweb/en/StatFin/StatFin__vaerak/statfin_vaerak_pxt_11rm.px/ |website=PxWeb |language=en |access-date=4 February 2024 }}</ref>

==History==
The idea of a universal second language is not new, and constructed languages are not a recent phenomenon. During the 12th century [[Hildegard of Bingen]] invented a set of words known as the [[Lingua Ignota]]. The concept did not attract significant interest until the language [[Volapük]] was created in 1879. Volapük was popular for some time and apparently had a few thousand users, but was later eclipsed by the popularity of [[Esperanto]], which was created in 1887. Several other languages, such as [[Latino sine flexione|Latino sine Flexione]] and [[Idiom Neutral]] were also proposed. It was during this time that French mathematician [[Louis Couturat]] formed the ''[[Delegation for the Adoption of an International Auxiliary Language]]''.

This delegation made a formal request to the [[International Association of Academies]] in [[Vienna]] to select and endorse an international language; the request was rejected in May 1907.<ref name="Guérard">{{cite book
|author=Guérard, A. L
|title=A Short History of the International Language Movement
|chapter=Chapter VII
|url=http://donh.best.vwh.net/Languages/delegation.html
|access-date=12 February 2012
|archive-url=https://web.archive.org/web/20120206141513/http://donh.best.vwh.net/Languages/delegation.html
|archive-date=6 February 2012
|url-status=dead
}}</ref> The Delegation then met as a Committee in Paris in October 1907 to discuss the adoption of a standard international language. Among the languages considered was a new language submitted anonymously after the Committee's deadline by someone using the name ''Ido''.<ref name="Dyer">{{cite book
|last=Dyer
|first=Luther H
|year=1923
|title=The Problem of an International Auxiliary Language and its Solution in Ido
|url=http://interlanguages.net/054_074.html
|pages=54–74
|access-date=12 February 2012
|archive-date=7 May 2018
|archive-url=https://web.archive.org/web/20180507073229/http://interlanguages.net/054_074.html
|url-status=live
}}</ref> In the end the committee, always without plenary sessions and consisting of only 12 members, concluded the last day with 4 votes for and 1 abstention. They concluded that no language was completely acceptable, but that Esperanto could be accepted "on condition of several modifications to be realized by the permanent Commission in the direction defined by the conclusions of the Report of the Secretaries [Louis Couturat and [[Léopold Leau]]] and by the Ido project".<ref>{{cite journal
|last=Leau
|first=Léopold
|date=August 1933
|journal=Progreso
|volume=X
|issue=96
|pages=4
|title=La Vereso pri la Delegitaro en 1907
|trans-title=The Truth about the Delegation in 1907
|language=io
|url=http://interlanguages.net/truth.html
|access-date=12 February 2012
|archive-date=27 March 2022
|archive-url=https://web.archive.org/web/20220327235950/http://interlanguages.net/truth.html
|url-status=live
}}</ref>

[[File:Ido Kongreso en Dessau 1922.jpg|thumb|300px|left|The International Ido Congress in [[Dessau]], Germany, in 1922.]]

Esperanto's inventor, [[L. L. Zamenhof]], having heard a number of complaints, had suggested in 1894 [[1894 Esperanto reform project|a proposal for a reformed Esperanto]] with several changes that Ido adopted: eliminating the accented letters and the [[accusative case]], changing the plural to an Italianesque ''-i'', and replacing the table of correlatives with more Latinate words. However, the Esperanto community voted and rejected Zamenhof's reformed Esperanto,<ref name="Dyer"/> and likewise most rejected the recommendations of the 1907 Committee composed nominally of 12 members. Zamenhof, undoubtedly reminiscent of his experience of the 1894 reforms, strongly supported the Esperanto Committee majority decision.<ref name=":0">{{Cite book |last=Garvia |first=Robert |title=Esperanto and Its Rivals |year=2015 |isbn=978-0-8122-4710-7 |pages=134–137|publisher=University of Pennsylvania Press }}</ref> Furthermore, controversy ensued when the "Ido project" was found to have been devised mainly by [[Louis de Beaufront]], whom Zamenhof had chosen to represent Esperanto to the committee (Zamenhof himself could not represent Esperanto as the committee's rules dictated that the creator of a submitted language could not defend it).<ref>{{cite book
|last=Jacob
|first=Henry
|year=1947
|title=A Planned Auxiliary Language
|chapter=II. Ido
|url=http://interlanguages.net/PALih.html
|access-date=12 February 2012
|archive-date=21 March 2012
|archive-url=https://web.archive.org/web/20120321170702/http://interlanguages.net/PALih.html
|url-status=live
}}</ref> The Committee's meetings were performed mainly in French, with occasional German.<ref name=":0" /> When the president of the Committee asked who was the author of Ido's project, Couturat, de Beaufront and Leau answered that they were not. De Beaufront presented Ido's project and gave a description of it as a better, richer version of Esperanto. Couturat, Leau, de Beaufront and Jespersen were finally the only members who voted, all of them for Ido's project. A month later, Couturat accidentally forwarded Jespersen a copy of a letter in which he acknowledged that de Beaufront was the author of the Ido project.<ref name=":0" /> Jespersen was angered by this and asked for a public confession. De Beaufront procrastinated for four months before making a public confession.<ref name=":0" />

It is estimated that some 20% of Esperanto's major promoters and 3–4% of ordinary Esperantists switched to Ido, which from then on suffered constant modifications seeking to perfect it, but which ultimately had the effect of causing many Ido speakers to abandoned trying to learn it.<ref>{{cite book
|last=Lapenna
|first=Ivo
|author-link=Ivo Lapenna
|author2=Ulrich Lins |author3=Tazio Carlevaro
|title=Esperanto en perspektivo: Faktoj kaj analizoj pri la internacia lingvo
|trans-title= Esperanto in Perspective: Facts and Analyses about the International Language
|year=1974
|language=eo
|location=London
|publisher=Centro de Esploro kaj Dokumentado pri la Monda Lingvo-Problemo
|pages=424
}}</ref> Although it divided the Esperanto movement, the schism gave the remaining Esperantists the freedom to concentrate on using and promoting their language as it was.<ref>{{cite web 
 |author=Harlow, Donald J 
 |author-link=Don Harlow 
 |url=http://literaturo.org/HARLOW-Don/Esperanto/EBook/chap03.html#ido 
 |title=Ido 
 |work=How to Build a Language 
 |date=4 July 2006 
 |access-date=12 February 2020 
 |archive-date=14 February 2020 
 |archive-url=https://web.archive.org/web/20200214162149/http://literaturo.org/HARLOW-Don/Esperanto/EBook/chap03.html#ido 
 |url-status=live 
 }}</ref> At the same time, it gave the Idists freedom to continue working on their own language for several more years before actively promoting it. The ''Uniono di la Amiki di la Linguo Internaciona'' (''Union of Friends of the International Language'') was established along with an Ido Academy to develop the details of the new language.<ref name="Dyer"/>

Couturat, who was the main proponent of Ido, was killed in an automobile accident in 1914.<ref name="Dyer"/> This, along with [[World War I]], practically suspended the activities of the Ido Academy from 1914 to 1920.<ref name="Guérard"/> In 1928 Ido's major intellectual promoter, the Danish linguist [[Otto Jespersen]], published his own planned language, [[Novial]] and ended his promotion of Ido.<ref>{{cite web 
 |author=Harlow, Donald J 
 |author-link=Don Harlow 
 |url=http://literaturo.org/HARLOW-Don/Esperanto/EBook/chap03.html 
 |title=How to Build a Language 
 |access-date=4 February 2019 
 |archive-date=22 December 2018 
 |archive-url=https://web.archive.org/web/20181222135928/http://literaturo.org/HARLOW-Don/Esperanto/EBook/chap03.html 
 |url-status=live 
 }}</ref>

===Digital era===
The language still has active speakers, numbering about 500.<ref>{{cite journal |last=Seagull |first=Gareth |date=2019-10-29 |title=Should there be a Universal Language? |url=https://raptortranslations.com/2019/10/29/should-be-a-universal-language/ |journal=Raptor Translations Magazine: The Translation Business Magazine |publisher=Raptor Consolidated Media Group |access-date=2021-01-05 |archive-date=10 November 2019 |archive-url=https://web.archive.org/web/20191110201636/https://raptortranslations.com/2019/10/29/should-be-a-universal-language/ |url-status=live }}</ref> The Internet has caused a renewal of interest in the language during recent years. A sample of 24 Idists on the [[Yahoo!]] group ''Idolisto'' during November 2005 showed that 57% had begun their studies of the language during the preceding three years, 32% from the mid-1990s to 2002, and 8% had known the language from before.<ref>{{cite web |last=MacLeod |first=Dave |date=23 November 2005 |title=Votez! Kande vu komencis lernar Ido? |trans-title=Vote! When did you start learning Ido? |url=https://groups.yahoo.com/group/idolisto/message/14569 |archive-url=https://archive.today/20120711235713/http://groups.yahoo.com/group/idolisto/message/14569 |url-status=dead |archive-date=11 July 2012 |access-date=19 January 2012 |language=io}}</ref>

===Changes===
Few changes have been made to Ido since 1922.<ref name="Chandler">{{cite web
|last=Chandler
|first=James
|date=6 November 1997
|title=Changes in Ido since 1922
|url=http://interlanguages.net/changes.html
|access-date=19 January 2012
|archive-date=27 March 2022
|archive-url=https://web.archive.org/web/20220327235948/http://interlanguages.net/changes.html
|url-status=live
}}</ref>

Camiel de Cock was named secretary of linguistic issues in 1990, succeeding Roger Moureaux.<ref>{{cite web
|title=Listo di nova vorti propozita da la Linguala komitato dil Uniono
|trans-title=List of new words proposed by the Language committee of the Union
|language=io
|url=http://www.reocities.com/Paris/Rue/8009/neologismi.htm
|work=Suplemento a la revuo Progreso numero 290
|publisher=ULI
|access-date=2012-04-19
|archive-url= https://web.archive.org/web/20120914031934/http://www.reocities.com/Paris/Rue/8009/neologismi.htm
|archive-date=2012-09-14
|url-status=dead
}}</ref> He resigned after the creation of a linguistic committee in 1991.<ref>{{cite web
|last=Bol
|first=Jacques
|title=Pri Camiel de Cock
|trans-title=About Camiel de Cock
|language=io
|url=https://groups.yahoo.com/group/idolisto/message/13008
|date=2004-11-15
|access-date=2 August 2016
|archive-date=26 October 2023
|archive-url=https://web.archive.org/web/20231026022557/https://www.yahoo.com/
|url-status=dead
}}</ref> De Cock was succeeded by Robert C. Carnaghan, who had the title from 1992 to 2008. No new words were adopted between 2001 and 2006.<ref>{{cite web
|last=Chandler
|first=James
|title=Lasta decido pri nova vorti
|trans-title= Latest decision on new words
|language=io
|url=http://tech.groups.yahoo.com/group/linguolisto/message/2384
|archive-url=https://archive.today/20120720022536/http://tech.groups.yahoo.com/group/linguolisto/message/2384
|url-status=dead
|archive-date=20 July 2012
|date=2006-04-16
}}</ref> After the 2008–2011 elections of ULI's direction committee, [[Gonçalo Neves]] replaced Carnaghan as secretary of linguistic issues during February 2008.<ref>{{cite web
|last=Landais
|first=Loïc
|title=Nova DK di ULI por 2008–2011
|trans-title= New SC ''[Steering Committee]'' of ULI for 2008-2011
|language=io
|url=http://tech.groups.yahoo.com/group/linguolisto/message/3151
|archive-url=https://archive.today/20120729181321/http://tech.groups.yahoo.com/group/linguolisto/message/3151
|url-status=dead
|archive-date=29 July 2012
|date=2008-02-17
}}</ref> Neves resigned during August 2008.<ref>{{cite web
|last=Neves
|first=Gonçalo
|title=demisiono ed adio
|trans-title=resignation and farewell
|language=io
|url=https://groups.yahoo.com/group/idolisto/message/17503
|date=2008-08-29
|access-date=2 August 2016
|archive-date=26 October 2023
|archive-url=https://web.archive.org/web/20231026022714/https://www.yahoo.com/
|url-status=dead
}}</ref> A new linguistic committee was formed in 2010.<ref>{{cite web
|last=Landais
|first=Loïc
|title=Linguala Komitato di ULI
|trans-title=Linguistic Committee of the ULI
|url=https://groups.yahoo.com/group/idolisto/message/20007
|language=io
|date=2009-09-28
|access-date=2 August 2016
|archive-date=26 October 2023
|archive-url=https://web.archive.org/web/20231026022559/https://www.yahoo.com/
|url-status=dead
}}</ref><ref>{{cite web
|last=Richard
|first=Gaël
|title=RE: <nowiki>[linguo]</nowiki> Ube es komitato linguala
|trans-title=RE: <nowiki>[language]</nowiki> Where is the language committee
|url=http://tech.groups.yahoo.com/group/linguolisto/message/3786
|archive-url=https://archive.today/20120716144627/http://tech.groups.yahoo.com/group/linguolisto/message/3786
|url-status=dead
|archive-date=16 July 2012
|language=io
|date=2010-02-09
}}</ref><ref>{{cite web
|title=Linguala Komitato di ULI
|trans-title=Linguistic Committee of the ULI
|url=http://www.ido.li/index.php/ULI/LingualaKomitato
|publisher=Uniono por la Linguo Internaciona Ido (ULI)
|access-date=19 April 2012
|archive-date=1 April 2012
|archive-url=https://web.archive.org/web/20120401104419/http://www.ido.li/index.php/ULI/LingualaKomitato
|url-status=live
}}</ref>  In April 2010, Tiberio Madonna was appointed as secretary of linguistic issues, succeeding Neves.<ref>{{cite web
|last=Jibran (Partaka )
|first=Khalil
|title=Ido havas nova Sekretario pri Linguala Questioni
|trans-title=Ido has a new Secretary of Linguistic Issues
|url=http://es.dir.groups.yahoo.com/group/posta_Mundi/message/5979 
|language=io
|archive-url =https://archive.today/20120712204722/http://es.dir.groups.yahoo.com/group/posta_Mundi/message/5979
|url-status=dead
|archive-date=2012-07-12
|date=2010-04-16
}}</ref><ref>{{cite web
|title=Nomino di Sekretario por Linguala Questioni di ULI
|trans-title=Nomination of the Secretariat for Linguistic Functions of the ULI
|url=http://www.ido.li/index.php/ULI/2010
|language=io
|work=Uniono por la Linguo Internaciona Ido
|date=2010-04-03
|access-date=19 April 2012
|archive-date=28 October 2012
|archive-url=https://web.archive.org/web/20121028114922/http://www.ido.li/index.php/ULI/2010
|url-status=live
}}</ref>  
In January 2011, ULI approved eight new words.<ref>{{cite web
|last=Madonna
|first=Tiberio
|title=2esma raporto de la Linguala Komitato
|trans-title= 2nd report of the Linguistic Committee
|language=io
|url=http://tech.groups.yahoo.com/group/linguolisto/message/3968
|archive-url=https://archive.today/20120716175811/http://tech.groups.yahoo.com/group/linguolisto/message/3968
|url-status=dead
|archive-date=16 July 2012
|date=2011-01-01
}}</ref> This was the first addition of words in many years.<ref>{{cite web
|last=Chandler
|first=James
|title=RE: <nowiki>[linguo]</nowiki> 2esma raporto de la Linguala Komitato
| trans-title= 2nd report of the Language committee
|language=io
|url=http://tech.groups.yahoo.com/group/linguolisto/message/3970
|archive-url=https://archive.today/20120716103628/http://tech.groups.yahoo.com/group/linguolisto/message/3970
|url-status=dead
|archive-date=16 July 2012
|date=2011-01-02
}}</ref> After a series of severe conflicts with the Directing Committee of ULI, Tiberio Madonna was revoked as secretary of linguistic issues on the 26th of May 2013 by official announcement from Loïs Landais, the secretary of ULI.<ref>Anunco di la DK pri Tiberio Madonna, ULI-IDO, yahoogroups, May 26th 2013</ref>
During January 2022, ULI approved a set of new words (34)<ref>Progreso 382 January–April 2022</ref>

==Phonology==
Ido has five vowel [[phoneme]]s. The values {{IPAblink|e|}} and {{IPAblink|ɛ||}} are interchangeable depending on speaker preference, as are {{IPAblink|o||}} and {{IPAblink|ɔ||}}. The orthographic sequences {{angbr|au}} and {{angbr|eu}} indicate [[diphthong]]s in word roots but not when created by affixing.<ref name="KGD7">{{cite web|url=http://ido-vivo.info/kgd.pdf#page=7 |title=Pronunco dil vokali |work=Kompleta Gramatiko detaloza di la linguo internaciona Ido |date=2004 |page=7 |archive-url=https://web.archive.org/web/20150813213123/http://ido-vivo.info/kgd.pdf#page=7 |archive-date=13 August 2015 |url-status=live |first=Louis |last=De Beaufront |editor-first=Fernando |editor-last=Tejón |language=io |publisher=Krayono |location=Ponferrada, Spain |orig-year=1st pub. 1925 |format=PDF }}</ref>

{| class="wikitable" style="text-align: center;"
|+ Ido vowels
!
! | [[Front vowel|Front]]
! | [[Back vowel|Back]]
|-
! [[Close vowel|Close]]
| {{IPA link|i}}
| {{IPA link|u}}
|-
! Mid
| {{IPA link|e}} ~ {{IPA link|ɛ}}
| {{IPA link|o}} ~ {{IPA link|ɔ}}
|-
! [[Open vowel|Open]]
| colspan=2 | {{IPA link|a}}
|}

{| class="wikitable" style="text-align: center;"
|-
|+Ido consonants
!
! colspan=2 Width=13% | [[Labial consonant|Labial]]
! colspan=2 Width=13% | [[Alveolar consonant|Alveolar]]
! colspan=2 Width=13% | [[Postalveolar consonant|Post-<br/>alveolar]]
! colspan=2 Width=13% | [[Palatal consonant|Palatal]]
! colspan=2 Width=13% | [[Velar consonant|Velar]]
! colspan=2 Width=13% | [[Glottal consonant|Glottal]]
|-
! [[Nasal consonant|Nasal]]
|style="border-right: 0;"| ||style="border-left: 0;"|{{IPA link|m}}
|style="border-right: 0;"| ||style="border-left: 0;"|{{IPA link|n}}
| colspan=2 |
| colspan=2 |
| colspan=2 |
| colspan=2 |
|-
! [[Stop consonant|Stop]]
|style="border-right: 0;"|{{IPA link|p}}||style="border-left: 0;"|{{IPA link|b}}
|style="border-right: 0;"|{{IPA link|t}}||style="border-left: 0;"|{{IPA link|d}}
| colspan=2 |
| colspan=2 |
|style="border-right: 0;"|{{IPA link|k}}||style="border-left: 0;"|{{IPA link|ɡ}}
| colspan=2 |
|-
! [[Affricate consonant|Affricate]]
| colspan=2 |
|style="border-right: 0;"|c {{IPAslink|t͡s}}|| style="border-left: 0;" |
|style="border-right: 0;"|ch {{IPAslink|t͡ʃ}}|| style="border-left: 0;" |
| colspan=2 |
| colspan=2 |
| colspan=2 |
|-
! [[Fricative consonant|Fricative]]
|style="border-right: 0;"|{{IPA link|f}}||style="border-left: 0;"|{{IPA link|v}}
|style="border-right: 0;"|{{IPA link|s}}||style="border-left: 0;"|{{IPA link|z}}
|style="border-right: 0;"|sh {{IPAslink|ʃ}}|| style="border-left: 0;" |j {{IPAslink|ʒ}}
| colspan=2 |
| colspan=2 |
|style="border-right: 0;"|{{IPA link|h}}||style="border-left: 0;"|
|-
! [[Approximant consonant|Approximant]]
|
|{{IPA link|w}}
| style="border-right: 0;" | ||style="border-left: 0;"|{{IPA link|l}}
| colspan=2 |
|style="border-right: 0;"| ||style="border-left: 0;"|y {{IPAslink|j}}
|style="border-right: 0;"| ||style="border-left: 0;"|({{IPA link|w}})
| colspan=2 |
|-
! [[Flap consonant|Flap]]
| colspan=2 |
|style="border-right: 0;"| ||style="border-left: 0;"|r {{IPAslink|ɾ}}
| colspan=2 |
| colspan=2 |
| colspan=2 |
| colspan=2 |
|}

All polysyllabic words are stressed on the second-to-last syllable except for verb [[infinitive]]s, which are stressed on the last syllable{{spnd}}'''sko'''lo, ka'''fe'''o and '''ler'''nas for "school", "coffee" and the present tense of "to learn", but i'''rar''', sa'''var''' and drin'''kar''' for "to go", "to know" and "to drink". If an '''i''' or '''u''' precedes another vowel, the pair is considered part of the same syllable when applying the accent rule{{spnd}}thus '''ra'''dio, fa'''mi'''lio and '''ma'''nuo for "radio", "family" and "hand", unless the two vowels are the only ones in the word, in which case the "i" or "u" is stressed: '''di'''o, '''fru'''a for "day" and "early".<ref>{{cite web
|url=http://www.literaturo.ido.li/kgd.pdf
|title=Acento tonika
|trans-title=Tonic accent
|last=De Beaufront
|first=L
|work=Kompleta Gramatiko Detaloza di Ido
|pages=11–12
|year=2004
|access-date=19 January 2012
|archive-date=6 February 2012
|archive-url=https://web.archive.org/web/20120206023705/http://www.literaturo.ido.li/kgd.pdf
|url-status=live
}}</ref>

==Orthography==
Ido uses the same 26 letters as the [[English alphabet]] and [[ISO Basic Latin alphabet]] with three [[Digraph (orthography)|digraphs]] and no [[Typographic ligature|ligatures]] or [[diacritics]]. Where the table below lists two pronunciations, either is perfectly acceptable.<ref name="Beaufront 7-18">{{cite web
|url=http://www.literaturo.ido.li/kgd.pdf
|title=Kompleta Gramatiko Detaloza di Ido
|trans-title=Comeplete Detailed Grammar of Ido
|last=De Beaufront
|first=L
|pages=7–10
|year=2004
|access-date=19 January 2012
|archive-date=6 February 2012
|archive-url=https://web.archive.org/web/20120206023705/http://www.literaturo.ido.li/kgd.pdf
|url-status=live
}}</ref>

{| class="wikitable"
! Letter
! IPA
! English
!Esperanto
|-
| a || {{IPAslink|a}} || ''a'' as in "p'''a'''rt"
|
|-
| b || {{IPAslink|b}} || ''b'' as in "sta'''b'''le"
|
|-
| c || {{IPAslink|t͡s}} || most similar to ''ts'' as in "ca'''ts'''"{{Break}}*(also used in the digraph ''ch'')
|
|-
| d || {{IPAslink|d}} || ''d'' as in "a'''d'''opt"
|
|-
| e || {{IPAslink|e}}, {{IPAslink|ɛ}} || most similar to ''e'' as in "'''e'''gg" or ''e'' as in "b'''e'''t"
|
|-
| f || {{IPAslink|f}} || ''f'' as in "a'''f'''raid"
|
|-
| g || {{IPAslink|ɡ}} || hard ''g'' as in "'''g'''o"
|
|-
| h || {{IPAslink|h}} || ''h'' as in "'''h'''at", "a'''h'''oy"
|
|-
| i || {{IPAslink|i}} || ''i'' as in "mach'''i'''ne", ''ee'' in "b'''ee'''"
|
|-
| j || {{IPAslink|ʒ}}, {{IPAslink|d͡ʒ}} || ''s'' as in "plea'''s'''ure, mea'''s'''ure" or ''g'' in "mira'''g'''e, bei'''g'''e"
|'''ĵ or ĝ'''
|-
| k || {{IPAslink|k}} || ''k'' as in "s'''k'''in, s'''k'''ip"
|
|-
| l || {{IPAslink|l}} || most similar to ''l'' as in "'''l'''amb"
|
|-
| m || {{IPAslink|m}} || ''m'' as in "ad'''m'''it"
|
|-
| n || {{IPAslink|n}} || ''n'' as in "a'''n'''alogy"
|
|-
| o || {{IPAslink|o}}, {{IPAslink|ɔ}} || most similar to ''o'' as in "'''o'''r"
|
|-
| p || {{IPAslink|p}} || ''p'' as in "s'''p'''in, s'''p'''ark"
|
|-
| q || {{IPAslink|k}} || same as ''k{{Break}}''*(used only in the digraph ''qu'')
| -
|-
| r || {{IPAslink|ɾ}} || flapped or rolled ''r'' as in [[Italian language|Italian]] or [[spanish language|Spanish]];{{Break}}or the ''r'' in ve'''r'''y in [[Scottish English]] pronunciation (cf ''[[Pronunciation of English /r/]]'')
|
|-
| s || {{IPAslink|s}} || ''s'' as in "ea'''s'''t"{{Break}}*(also used in the digraph ''sh'')
|
|-
| t || {{IPAslink|t}} || ''t'' as in "s'''t'''ake, s'''t'''op"
|
|-
| u || {{IPAslink|u}} || ''u'' as in "r'''u'''de"
|
|-
| v || {{IPAslink|v}} || ''v'' as in "a'''v'''oid"
|
|-
| w || {{IPAslink|w}} || ''w'' as in "a'''w'''ard"
| -
|-
| x || {{IPA|/ks/}}, {{IPA|/ɡz/}} || x as in "e'''x'''cept" or "e'''x'''ist"
| -
|-
| y || {{IPAslink|j}} || ''y'' as in "'''y'''es"
|j
|-
| z || {{IPAslink|z}} || ''z'' as in "'''z'''ebra"
|
|}

The digraphs are:<ref name="Beaufront 7-18"/>

{| class="wikitable"
! Digraph
! IPA
! English
!Esperanto
|-
| ch || {{IPAslink|t͡ʃ}} || ''ch'' as in "'''ch'''ick"
|'''ĉ'''
|-
| qu || {{IPA|/kw/}}, {{IPA|/kv/}} || ''qu'' as in "'''qu'''ick"
| -
|-
| sh || {{IPAslink|ʃ}} || ''sh'' as in "'''sh'''y"
|'''ŝ'''
|}

==Grammar==
The definite article is ''la'' and is invariable.  The indefinite article (a/an) does not exist in Ido. Each word in the Ido vocabulary is built from a root word. A word consists of a root and a grammatical ending. Other words can be formed from that word by removing the grammatical ending and adding a new one, or by inserting certain [[affix]]es between the root and the grammatical ending.

Some of the grammatical endings are defined as follows:

{| class="wikitable"
|-
! Grammatical form
 ! Ido
 
! colspan="2" |Esperanto
! colspan=2 | English
 
|-
! [[Noun|Singular noun]]
| ''' -o''' (libro)
 
| colspan="2" |'''-o''' (libro)
| colspan=2 | '''-''' (book)
 
|-
! [[Noun|Plural noun]]
 | '''-i''' (libri)
 
| colspan="2" |'''-oj''' (libroj)
| colspan=2 | '''-s''' (books)
 
|-
! [[Adjective]]
 | '''-a''' (varma)
 
| colspan="2" |'''-a''', '''-aj''' (varma, varmaj)
| colspan=2 | '''-''' (warm)
 
|-
! [[Adverb]]
 | '''-e''' (varme)
 
| colspan="2" |'''-e''' (varme)
| colspan=2 | -ly (warmly)
 
|-
! [[Infinitive|Present tense infinitive]]
| '''-ar''' (irar)
 
|'''-anti''' (iranti)
| rowspan="3" |'''-i''' (iri)
| to be - (to be going)
 
| rowspan=3 | '''to -''' (to go)
 
|-
! [[Infinitive|Past tense infinitive]]
| '''-ir''' (irir)
 
|'''-inti''' (irinti)
| to have - (to have gone)
 
|-
! [[Infinitive|Future tense infinitive]]
| '''-or''' (iror)
 
|'''-onti''' (ironti)
| to be going to - (to be going to go)
 
|-
! [[Present tense|Present]]
| '''-as''' (iras)
 
| colspan="2" |'''-as''' (iras)
| colspan=2 | -, -s, -es (go, goes)
 
|-
! [[Past tense|Past]]
| '''-is''' (iris)
 
| colspan="2" |'''-is''' (iris)
| colspan=2 | irr., -ed (went)
 
|-
! [[Future tense|Future]]
| '''-os''' (iros)
 
| colspan="2" |'''-os''' (iros)
| colspan=2 | will - (will go)
 
|-
! [[Imperative mood|Imperative]]
| '''-ez''' (irez)
 
| colspan="2" |'''-u''' (iru)
| colspan=2 | ! (go!)
 
|-
! [[Conditional mood|Conditional]]
| '''-us''' (irus)
 
| colspan="2" |'''-us''' (irus)
| colspan=2 | would - (would go)
 
|}

These are the same as in Esperanto except for ''-i'', ''-ir'', ''-ar'', ''-or'' and ''-ez''. Esperanto marks noun plurals by an ''agglutinative'' ending ''-j'' (so plural nouns end in ''-oj''), uses ''-i'' for verb infinitives (Esperanto infinitives are tenseless), and uses ''-u'' for the imperative. Verbs in Ido, as in Esperanto, do not conjugate depending on person, number or gender; the -'''as''', -'''is''', and -'''os''' endings suffice whether the subject is I, you, he, she, they, or anything else. For the word "to be," Ido allows either ''esas'' or ''es'' in the present tense; however, the full forms must be used for the past tense ''esis'' and future tense ''esos''."  Adjectives and adverbs are compared in Ido by means of the words ''plu'' = more, ''maxim'' = most, ''min'' = less, ''minim'' = least, ''kam'' = than/as. There exist in Ido three categories of adverbs: the simple, the derived, and the composed. The simple adverbs do not need special endings, for example: ''tre'' = very, ''tro'' = too, ''olim'' = formerly, ''nun'' = now, ''nur'' = only. The derived and composed adverbs, not being originally adverbs but derived from nouns, adjectives and verbs, have the ending '''-e'''.

===Syntax===
Ido word order is generally the same as English ([[subject–verb–object]]), so the sentence ''Me havas la blua libro'' is the same as the English "I have the blue book", both in meaning and word order. There are a few differences, however:
* Adjectives can precede the noun as in English, or follow the noun as in Spanish. Thus, ''Me havas la libro blua'' means the same thing.
* Ido has the [[accusative]] suffix ''-n''. Unlike Esperanto, this suffix is only required when the object of the sentence is not clear, for example, when the subject-verb-object word order is not followed. Thus, ''La blua libron me havas'' also means the same thing.

Ido generally does not impose rules of grammatical [[Agreement (linguistics)|agreement]] between grammatical categories within a sentence. For example, the verb in a sentence is invariable regardless of the number and person of the subject. Nor must the adjectives be pluralized as well the nouns{{spnd}}in Ido ''the large books'' would be ''la granda libri'' as opposed to the Esperanto ''la grandaj libroj''.

Negation occurs in Ido by simply adding '''ne''' before a verb: '''Me ne havas libro''' means "I do not have a book". This as well does not vary, and thus the "I do not", "He does not", "They do not" before a verb are simply '''Me ne''', '''Il ne''', and '''Li ne'''. In the same way, past tense and future tense negatives are formed by '''ne''' before the conjugated verb. "I will not go" and "I did not go" become '''Me ne iros''' and '''Me ne iris''' respectively.

Yes/no questions are formed by the particle '''ka''' in front of the question. "I have a book" (me havas libro) becomes '''Ka me havas libro?''' (do I have a book?). '''Ka''' can also be placed in front of a noun without a verb to make a simple question, corresponding to the English "is it?" '''Ka Mark?''' can mean, "Are you Mark?", "Is it Mark?", "Do you mean Mark?" depending on the context.

===Pronouns===
The [[pronoun]]s of Ido were revised to make them more distinct acoustically than those of Esperanto, which all end in ''i''. Especially the singular and plural first-person pronouns ''mi'' and ''ni'' may be difficult to distinguish in a noisy environment, so Ido has ''me'' and ''ni'' instead. Ido also distinguishes between [[T-V distinction|intimate (''tu'') and formal (''vu'')]] second-person singular pronouns as well as plural second-person pronouns (''vi'') not marked for intimacy. Furthermore, Ido has a pan-gender third-person pronoun ''lu'' (it can mean "he", "she", or "it", depending on the context) in addition to its masculine (''il''), feminine (''el''), and neuter (''ol'') third-person pronouns.

{| class="wikitable" style="text-align:center"
|+ Pronouns
!rowspan="3"|
!colspan="7"|singular
!colspan="6" |plural
!rowspan="3"|reflexive
!rowspan="3"|indefinite
|-
!rowspan="2"|first
!colspan="2"|second
!colspan="4"|third
!rowspan="2"|first
!rowspan="2"|second
!colspan="4"|third
|-
!''familiar''
!''formal''
!''masc.''
!''fem.''
!''neuter''
!''pan-gender''
!''masc.''
!''fem.''
!''neuter''
!''pan-gender''
|-
!Ido
| me
| tu
| vu
| il(u)
| el(u)
| ol(u)
| lu
| ni
| vi
| ili
| eli
| oli
| li
| su
| on(u)
|-
!English
| I
| [[thou]]
| you
| he
| she
| it
| they/it
| we
| you
|
|
|
| they
|oneself
| one/you/they
|-
!Esperanto
| mi
| ci¹
| vi¹
| li
| ŝi
| ĝi
| ĝi/ri²
| ni
| vi
| ili
|iŝi²
|iĝi²
| ili/iri²
| si
| oni
|}
# ''ci'', although technically the familiar form of the word "you" in Esperanto, is seldom used. Esperanto's inventor himself did not include the pronoun in the first book on Esperanto and only later reluctantly; later he recommended against using ''ci'' because different cultures have conflicting traditions regarding the use of the familiar and formal forms of "you".<ref>Eventoj, no. 103, {{ISSN|1215-959X}}. ''Ci'' estas senvalora balasto (''Ci'' is useless ballast). 1996. Available at http://www.eventoj.hu/arkivo/eve-103.htm {{Webarchive|url=https://web.archive.org/web/20060108045107/http://www.eventoj.hu/arkivo/eve-103.htm |date=8 January 2006 }}</ref>
#''ri'', ''iŝi'', ''iĝi'' and by extension ''iri'' are proposed neologisms and are rare, but they are still used albeit seldom.

''ol'', like English ''it'' and Esperanto ''ĝi'', is not limited to inanimate objects, but can be used "for entities whose sex is indeterminate: ''babies, children, humans, youths, elders, people, individuals, horses, [cattle], cats,'' etc."

''Lu'' is often mistakenly labeled an [[epicene]] pronoun, that is, one that refers to both masculine and feminine beings, but in fact, ''lu'' is more properly a "pan-gender" pronoun, as it is also used for referring to inanimate objects. From ''Kompleta Gramatiko Detaloza di la Linguo Internaciona Ido'' by Beaufront:

{{Blockquote|
''Lu'' (like ''li'') is used ''for all three genders.'' That ''lu'' does duty for the three genders at will in the singular is not in itself any more astonishing than seeing ''li'' serve the three genders at will in the plural ... By a decision (1558) the Idist Academy rejected every restriction concerning the use of ''lu.'' One may thus use that pronoun in exactly the same way for a thing and a person of obvious sex as for animals of unknown sex and a person that has a genderless name, like ''baby, child, human,'' etc., these being as truly masculine as feminine.
<br />
<br />
The motives for this decision were given in "Mondo", XI, 68: ''Lu'' for the singular is exactly the same as ''li'' for the plural. Logic, symmetry and ease demand this. Consequently, just as ''li'' may be used for people, animals, and objects whenever nothing obliges one to express the gender, so ''lu'' may be used for people, animals, and objects by the same condition. The proposed distinction would be a bothersome subtlety&nbsp;...
}}

===Table of correlatives===
Ido makes correlatives by combining entire words together and changing the word ending, with some irregularities to show distinction.
{| class="wikitable" style="text-align:center"
! rowspan="2" colspan="2" |
!Relative and<br>interrogative
!Demonstrative
!Indeterminate
!Most<br>Indeterminate
!Negative
!Collective
|-
!qua, ∅
!ita, ∅
!ula, ∅
!irga
!nula
!omna
|-
!Individual
!-u
| style="background: #fff1d8" | qua
| style="background: #fff1d8" | ita <sup>1</sup>
|ulu
|irgu
|nulu
|omnu
|-
!Plural
!-i
|qui
|iti <sup>1</sup>
|uli
|irgi
|nuli
|omni
|-
!Thing
!-o
|quo
|ito <sup>1</sup>
|ulo
|irgo
|nulo
|omno
|-
!Adjective
!-a
| style="background: #fff1d8" | qua
| style="background: #fff1d8" | ita <sup>1</sup>
|ula
|irga
|nula
|omna
|-
!Motive
!pro
|pro quo
|pro to
|pro ulo
|pro irgo
|pro nulo
|pro omno
|-
!Place
!loke
| style="background: #ffd8d8" | ube
| style="background: #ffd8d8" | ibe
|ulaloke
|irgaloke
|nulaloke
|omnaloke
|-
!Time
!tempe
| style="background: #ffd8d8" | kande
| style="background: #ffd8d8" | lore
|ulatempe <sup>2</sup>
|irgatempe
|nulatempe <sup>2</sup>
| style="background: #d8ffd8" | sempre <sup>3</sup>
|-
!Quality
!-a, speca
| style="background: #ffd8d8" | quala
| style="background: #ffd8d8" | tala
|ulaspeca <sup>2</sup>
|irgaspeca
|nulaspeca <sup>2</sup>
|omnaspeca
|-
!Manner
!-e, maniere
| style="background: #ffd8d8" | quale
| style="background: #ffd8d8" | tale
|ule, ulamaniere <sup>2</sup>
|irge, irgamaniere
|nule, nulamaniere <sup>2</sup>
|omne, omnamaniere
|-
!Quantity -<br>adjective
!quanta
| style="background: #ffd8d8" | quanta
| style="background: #ffd8d8" | tanta
| style="background: #ffd8d8" | kelka
|irgaquanta
|nulaquanta
|omnaquanta
|-
!Quantity -<br>noun
!quanto
| style="background: #ffd8d8" | quanto
| style="background: #ffd8d8" | tanto
| style="background: #ffd8d8" | kelko
| style="background: #d8ffd8" | irga quanto <sup>4</sup>
| style="background: #d8ffd8" | nula quanto <sup>4</sup>
| style="background: #d8ffd8" | la tota quanto <sup>4</sup>
|}

# The initial ''i'' can be omitted: ''ta'', ''to'', ''ti'', ''ta''.
# One can omit the initial ''a'': ''ultempe'', ''nultempe'', ''ulspeca'', ''nulspeca'', ''ulmaniere'', ''nulmaniere''.
# ''omnatempe'' is correct and usable, but ''sempre'' is the actual word.
# Instead of ''irga quanto'', ''nula quanto'' and ''la tota quanto'' one usually says ''irgo'', ''nulo'' and ''omno''.
{{anchor|Compounds formation}}

===Compound formation===

Composition in Ido obeys stricter rules than in Esperanto, especially formation of nouns, adjectives and verbs from a radical of a different class.  The reversibility principle assumes that for each composition rule (affix addition), the corresponding decomposition rule (affix removal) is valid.

Hence, while in Esperanto an adjective (for instance {{lang|eo|papera}}), formed on the noun radical {{lang|eo|paper(o)}}, can mean an attribute ({{lang|eo|papera enciklopedio}} "paper-made encyclopedia") and a relation ({{lang|eo|papera fabriko}} "paper-making factory"), Ido will distinguish the attribute {{lang|io|papera}} ("paper" or "of paper" (not "paper-made" exactly)) from the relation {{lang|io|paper'''al'''a}} ("paper-making").

Similarly, {{lang|eo|krono}} means in both Esperanto and Ido the noun "crown"; where Esperanto allows formation of "to crown" by simply changing the ending from noun to verb {{lang|eo|kroni}} ("crowning" is {{lang|eo|kronado}}), Ido requires an affix so the composition is reversible: {{lang|io|kron'''iz'''ar}} ("the act of crowning" is {{lang|io|kron'''iz'''o}}).

According to [[Claude Piron]], some modifications brought by Ido are in practice impossible to use and ruin spontaneous expression: 
<blockquote>
Ido displays, on linguistic level, other drawbacks Esperanto succeeded to avoid, but I don't have at hand documents which would allow me to go further in detail.  For instance, if I remember correctly, where Esperanto only has the suffix {{lang|eo|-igi}}*, Ido has several: *{{lang|io|-ifar}}*, *{{lang|io|-izar}}*, *{{lang|io|-igar}}*, which match subtleties which were meant to make language clearer, but that, in practice, inhibit natural expression.<ref>{{cite web| url = http://claudepiron.free.fr/lettresouvertes/ido.htm| title = Claude Piron - communication, langues, espéranto| access-date = 1 November 2018| archive-date = 22 May 2011| archive-url = https://web.archive.org/web/20110522212034/http://claudepiron.free.fr/lettresouvertes/ido.htm| url-status = live}}</ref>
</blockquote>

==Vocabulary==
{{see also|wiktionary:Appendix:Ido Swadesh list}}
Vocabulary in Ido is derived from French, Italian, Spanish, English, German, and Russian. Basing the vocabulary on various widespread languages was intended to make Ido as easy as possible for the greatest number of people possible. Early on, the first 5,371 Ido word roots were analyzed compared to the vocabulary of the six source languages, and the following result was found:<ref>{{cite book
|last=Dyer
|first=Luther H
|year=1923
|title=The Problem of an International Auxiliary Language and its Solution in Ido
|url=http://interlanguages.net/101_121.htm
|pages=101–121
|access-date=19 January 2012
|archive-date=2 March 2014
|archive-url=https://web.archive.org/web/20140302083436/http://interlanguages.net/101_121.htm
|url-status=live
}}</ref>

* 2024 roots (38%) belong to 6 languages
* 942 roots (17%) belong to 5 languages
* 1111 roots (21%) belong to 4 languages
* 585 roots (11%) belong to 3 languages
* 454 roots (8%) belong to 2 languages
* 255 roots (5%) belong to 1 language

Another analysis showed that:

* 4880 roots (91%) are found in French
* 4454 roots (83%) are found in Italian
* 4237 roots (79%) are found in Spanish
* 4219 roots (79%) are found in English
* 3302 roots (61%) are found in German
* 2821 roots (52%) are found in Russian

{| class="wikitable"
|+ Comparison of Ido vocabulary with its six source languages (by # of roots)
|-
! Ido 
!French!! colspan="2" | Italian !! colspan="2" | Spanish 
! colspan="2" |English!! colspan="2" | German !! colspan="2" | Russian 
|-
! bona
|bon|| colspan="2" | buono || colspan="2" | bueno 
|good
|bonus|| gut 
|Bonus|| khoroshiy 
|(хороший)
|-
! donar
|donner|| dare 
|donare|| dar 
|donar
|give
|donate|| colspan="2" | geben || dat, darit 
|(дать) (дарить)
|-
! filtrar
|filtrer|| colspan="2" | filtrare || colspan="2" | filtrar 
| colspan="2" |filter|| colspan="2" | filtern || filtrovat 
|(фильтровать)
|-
! gardeno
|jardin|| colspan="2" | giardino || colspan="2" | jardín 
| colspan="2" |garden|| colspan="2" | Garten || sad 
|(caд)
|-
! kavalo
|cheval|| colspan="2" | cavallo || colspan="2" | caballo 
|horse
|cavalry|| Pferd 
|Kavallerie|| loshad, kobyla 
|(лошадь, кобыла)
|-
! maro
|mer|| colspan="2" | mare || colspan="2" | mar 
|sea
|marine|| colspan="2" | Meer || more 
|(море)
|-
! naciono
|nation|| colspan="2" | nazione || colspan="2" | nación 
| colspan="2" |nation|| colspan="2" | Nation || natsija 
|(нация)
|-
! studiar
|étudier|| colspan="2" | studiare || colspan="2" | estudiar 
| colspan="2" |study|| colspan="2" | studieren || izuchat 
|(изучать)
|-
! yuna
|jeune|| colspan="2" | giovane || colspan="2" | joven 
|young
|juvenile|| colspan="2" | jung || yunyi, molodoy 
|(юный, молодой)
|}
{| class="wikitable"
|+Comparison of Ido vocabulary with Esperanto and Latin (or Germanic root)
!Ido
!Esperanto
!Latin
!Germanic
|-
!bona
|bona
|bonum
|
|-
!donar
|doni
|dare
|
|-
!filtrar
|filtri
|spargere
|felt
|-
!gardeno
|ĝardeno
|hortum
|gardo
|-
!kavalo
|ĉevalo
|equum, caballus
|
|-
!maro
|maro
|mare
|
|-
!naciono
|nacio
|gentem, natio
|
|-
!studiar
|studi
|studere
|
|-
!yuna
|juna
|iuvenis
|jung
|}
Vocabulary in Ido is often created through a number of official prefixes and suffixes that alter the meaning of the word. This allows a user to take existing words and modify them to create [[neologism]]s when necessary, and allows for a wide range of expression without the need to learn new vocabulary each time. Though their number is too large to be included in one article, some examples include:
*The diminutive suffix '''-et-'''. '''Domo''' (house) becomes '''dometo''' (cottage), and '''libro''' (book) becomes '''libreto''' (novelette or short story).
*The pejorative suffix '''-ach-'''. '''Domo''' becomes '''domacho''' (hovel), and '''libro''' becomes '''libracho''' (a shoddy piece of work, pulp fiction, etc.)
*The prefix '''retro-''', which implies a reversal. '''Irar''' (to go) becomes '''retroirar''' (to go back, backward) and '''venar''' (to come) becomes '''retrovenar''' (to return).

New vocabulary is generally created through an analysis of the word, its [[etymology]], and reference to the six source languages. If a word can be created through vocabulary already existing in the language then it will usually be adopted without need for a new radical (such as '''wikipedio''' for ''Wikipedia'', which consists of '''wiki''' + '''enciklopedio''' for ''encyclopedia''), and if not then an entirely new word will be created. The word '''alternatoro''' for example was adopted in 1926, likely because five of the six source languages used largely the same [[orthography]] for the word, and because it was long enough to avoid being mistaken for other words in the existing vocabulary.<ref>{{cite web
|url=http://interlanguages.net/nova.html
|title=Lexiko di nova vorti
|trans-title=Lexicon of new words
|author=De Cock, Camiel
|year=1988
|access-date=19 January 2012
|archive-date=11 October 2017
|archive-url=https://web.archive.org/web/20171011125713/http://interlanguages.net/nova.html
|url-status=live
}}</ref> Adoption of a word is done through consensus, after which the word will be made official by the [[Uniono por la Linguo Internaciona Ido|union]]. Care must also be taken to avoid [[homonym]]s if possible, and usually a new word undergoes some discussion before being adopted. Foreign words that have a restricted sense and are not likely to be used in everyday life (such as the word ''[[intifada]]'' to refer to [[Israeli–Palestinian conflict|the conflict]] between [[Israel]] and [[Palestinian territories|Palestine]]) are left untouched, and often written in italics.

Ido, unlike Esperanto, does not assume the male sex by default. For example, Ido does not derive the word for "waitress" by adding a feminine suffix to "waiter", as Esperanto does. Instead, Ido words are defined as [[Neuter (grammar)|sex-neutral]], and two different suffixes derive masculine and feminine words from the root: ''{{lang|io|servisto}}'' for a waiter of either sex, ''{{lang|io|servistulo}}'' for a male waiter, and ''{{lang|io|servistino}}'' for a waitress. There are only two exceptions to this rule:<ref name="Chandler"/> First, ''{{lang|io|patro}}'' for "father", ''{{lang|io|matro}}'' for "mother", and ''{{lang|io|genitoro}}'' for "parent", and second, ''{{lang|io|viro}}'' for "man", ''{{lang|io|muliero}}'' for "woman", and ''{{lang|io|adulto}}'' for "adult".<ref>{{cite book|url=http://idomondo.org/skolo.1.6.pdf#page=42 |title=Ido for All |date=2008 |pages=42,&nbsp;52,&nbsp;70 |archive-url=https://web.archive.org/web/20111125103925/http://idomondo.org/skolo.1.6.pdf#page=42 |archive-date=25 November 2011 |url-status=dead |first1=Niklas |last1=ApGawain |first2=P.&nbsp;D. |last2=Hugon |first3=J.&nbsp;L. |last3=Moore |first4=Louis |last4=De Beaufront |editor-first=Jerry |editor-last=Muelver |publisher=North American Ido Society |edition=1.6 |orig-year=1st pub. 1999 |format=PDF }}</ref>

==Sample==
{{listen
|filename=Padrenuestro.ogg
|title=The Lord's Prayer in Ido
}}
[[The Lord's Prayer]]:

{|
| style="padding-left:1em" | '''Ido'''{{Citation needed|date=April 2021}}
Patro nia, qua esas en la cielo,<br/>
tua nomo santigesez;<br/>
tua regno advenez;<br/>
tua volo facesez<br/>
quale en la cielo, tale anke sur la tero.<br/>
Donez a ni cadie [[Elided|l'omnadia]] pano,<br/>
e pardonez a ni nia ofensi,<br/>
quale anke ni pardonas a nia ofensanti,<br/>
e ne duktez ni aden la tento,<br/>
ma liberigez ni del malajo.<br/>
| style="padding-left:2em" | '''English'''
Our Father, who art in heaven,<br/>
hallowed be your name.<br/>
Thy kingdom come,<br/>
Thy will be done,<br/>
on earth as it is in heaven.<br/>
Give us this day our daily bread,<br/>
and forgive us our debts,<br/>
as we also have forgiven our debtors.<br/>
And lead us not into temptation,<br/>
but deliver us from evil.<br/>
|}

==Literature and publications==
Ido has a number of publications that can be subscribed to or downloaded for free in most cases. {{lang|io|Kuriero Internaciona}} is a magazine produced in France every few months with a range of topics. {{lang|io|Adavane!}} is a magazine produced by the Spanish Ido Society every two months that has a range of topics, as well as a few dozen pages of work translated from other languages. {{lang|io|Progreso}} is the official organ for the language and has existed since the ibeginning of Idoism in 1908. Other sites can be found with various stories, fables or proverbs along with a few books of the Bible translated into Ido on a smaller scale. The site {{lang|io|publikaji}} has a few podcasts in Ido along with various songs and other recorded material.

[[Wikipedia]] includes an [http://io.wikipedia.org/ Ido-language edition] (known in Ido as {{lang|io|Wikipedio}}); in 2018 it was the 93rd most visited Wikipedia,<ref>{{cite web
|url=http://stats.wikimedia.org/EN/TablesPageViewsMonthly.htm
|title=Page Views for Wikipedia, Non-mobile, Normalized
}}</ref> and is second most viewed Wikipedia edition in artificial language (after Esperanto).<ref name="Artificial">{{cite web |title=Page Views for Wikipedia for Artificial, Non-mobile site, Normalized |url=https://stats.wikimedia.org/EN_Artificial/TablesPageViewsMonthly.htm |website=stats.wikimedia.org}}</ref>

==Symbols of Ido==

[[File:Jankó-stelo (blue).svg|thumb|An Ido-Stelo]]

The [[:io:Ido-stelo|Ido star]] or [[Paul von Jankó|Jankó]] star is the main symbol of Ido. It is a six pointed star, with the points representing Ido's six source languages: English, French, Italian, German, Spanish and Russian. Alternatively, the six points represent the six [[continents]] (excluding Antarctica). The emblem was originally a six pointed white star on a circular blue background, consisting of two concentric, equilateral triangles, with one vertically flipped. However, this was soon changed due to the similarity it presented with the [[Star of David]], since a true [[international auxiliary language]] should not have religious affiliations.

After a search to find an appropriate new symbol, the [[Uniono por la Linguo Internaciona Ido|Ido-Akademio]] decided on the current Ido symbol, created by their secretary, [[Paul von Jankó]] (hence the alternative name the Jankó star). The current Ido Star is a [[Concave polygon|concave]] [[Isotoxal figure|isotoxal]] [[hexagon]], with a vertically flipped equilateral triangle overlaid on top.

==International Ido conventions==
[[Uniono por la Linguo Internaciona Ido|ULI]] organises Ido conventions yearly, and the conventions include a mix of tourism and work.<ref>{{cite web
|title=ULI's website
|url=http://www.uli-ido.ovh/ULI/index.php?page=ido-hodie
|access-date=10 January 2016
|archive-url=https://web.archive.org/web/20160304081040/http://www.uli-ido.ovh/ULI/index.php?page=ido-hodie
|archive-date=4 March 2016
|url-status=dead
}}</ref>
{{div col|colwidth=15em}}
* 2024: [[Madrid]], Spain ([https://www.idohispania.com])
* 2023: [[Kassel]], Germany ([http://www.ido.li/index.php/ULI/Idorenkontro2023])
* 2022: [[Dessau]], Germany, 15 participants([http://www.ido.li/index.php/ULI/Idorenkontro2022])
* 2019: Berlin, Germany, 15 participants from 2 countries ([http://www.ido.li/index.php/ULI/Idorenkontro2019 Information])
* 2018: [[Provins]], France, 11 participants from 5 countries ([http://www.ido.li/index.php/ULI/Idorenkontro2018 Information])
* 2017: [[České Budějovice]], [[Czech Republic]], 8 participants from 5 countries ([http://www.ido.li/index.php/ULI/Idorenkontro2017 Information])
* 2016: [[Valencia]], Spain, 10 participants from 7 countries ([https://web.archive.org/web/20160412101145/http://www.uli-ido.ovh/ULI/index.php?page=internaciona-renkontro-2016 Information])
* 2015: Berlin, Germany, 14 participants ([http://www.ido.li/index.php/ULI/IR2015 Information])
* 2014: Paris, France ([http://www.ido.li/index.php/ULI/Paris2014 Information])
* 2013: [[Ouroux-en-Morvan]], France, 13 participants from 4 countries ([http://www.ido.li/index.php/ULI/Ouroux2013 Information])
* 2012: [[Dessau]], Germany, 12 participants ([http://www.ido.li/index.php/ULI/Dessau2012 Information])
* 2011: [[Echternach]], Luxembourg ([http://www.ido.li/index.php/ULI/IR2011 Information]), 24 participants from 11 countries
* 2010: [[Tübingen]], Germany ([http://www.ido.li/index.php/ULI/IR2010 Information])
* 2009: [[Riga]], [[Latvia]], and [[Tallinn]], [[Estonia]], 14 participants from 7 countries ([http://www.ido.li/index.php/ULI/Tallin2009 Information])
* 2008: [[Wuppertal]]-[[Neviges]], Germany, 18 participants from 5 countries ([http://www.idolinguo.de/Idorenkontro2008/ Information])
* 2007: Paris, France, 14 participants from 9 countries ([http://www.ido.li/Idorenkontro2007/ Information],  [https://plus.google.com/photos/117431545220080970838/albums/5131141749857219169 Photos])
* 2006: Berlin, Germany, approx. 25 participants from 10 countries ([http://www.idolinguo.de/index.php/DIG/IdoKonfereo2006 Information])
* 2005: [[Toulouse]], France, 13 participants from 4 countries ([http://www.europa.idolinguo.com/Francia/Idorenkontro2005/ Information])
* 2004: Kyiv, [[Ukraine]], 17 participants from 9 countries ([http://www.europa.idolinguo.com/Ukrainia/Idorenkontro2004/ Information])
* 2003: [[Großbothen]], Germany, participants from 6 countries ([http://www.europa.idolinguo.com/Germania/Idokonfero2003/ido.htm Information])
* 2002: [[Kraków]], Poland, 14 participants from 6 countries ([http://www.europa.idolinguo.com/Polonia/krakow2002.htm Information])
* 2001: Nuremberg, Germany, 14 participants from 5 countries ([http://www.nefkom.net/frank.kasper/konf2001.htm Information])
* 2000: [[Nuremberg]], Germany
* 1999: Waldkappel, Germany
* 1998: [[Białobrzegi]], Poland, 15 participants from 6 countries
* 1997: [[Bakkum]], Netherlands, 19 participants from 7 countries
* 1995: [[Elsnigk]], Germany
* 1991: [[Ostend]], Belgium, 21 participants
* 1990: [[Waldkappel]], Germany
* 1989: Zürich-[[Thalwil]], Switzerland
* 1987: [[Eschwege]], Germany
* 1985: [[Antwerp]], Belgium
* 1983: [[York]], England
* 1981: [[Jongny]], Switzerland
* 1980: [[Namur]], Belgium, 35 participants
* 1979: [[Uppsala]], Sweden
* 1978: [[Cambridge]], England
* 1977: [[Berlin-Tegel]], Germany
* 1976: [[Saint-Nazaire]], France
* 1975: Thun, Switzerland
* 1974: [[Kyiv]], Ukraine
* 1973: [[Cardiff]], Wales
* 1972: [[Chaux-de-Fonds]], Switzerland
* 1971: [[Trollhättan]], [[Sweden]]
* 1970: [[Luxembourg City]], Luxembourg
* 1969: Zürich, Switzerland
* 1968: Berlin, Germany
* 1967: [[Bourges]], France
* 1966: [[Biella]], Italy
* 1965: [[Lons-le-Saunier]], France
* 1964: [[Kiel]], Germany
* 1963: [[Barcelona]], [[Spain]]
* 1962: [[Thun]], Switzerland
* 1961: Zürich, Switzerland, {{circa|50}} participants
* 1960: Colmar, France
* 1959: [[Freiburg im Breisgau]], Germany
* 1957: [[Luxembourg City]], Luxembourg
* 1952: [[Berlin]], Germany
* 1951: Turin, Italy
* 1950: [[Colmar]], France
* 1939: [[St. Gallen]], Switzerland
* 1937: Paris, France
* 1936: [[Szombathely]], Hungary
* 1935: [[Fredericia]], [[Denmark]]
* 1934: [[Oostduinkerke]], Belgium
* 1933: [[Mondorf]], Luxembourg
* 1931: [[Lauenburg/Elbe]], Germany
* 1930: [[Sopron]], [[Hungary]]
* 1929: [[Freiburg im Breisgau]], Germany
* 1928: [[Zürich]], [[Switzerland]]
* 1927: [[Paris]], [[France]]
* 1926: [[Prague]], [[Czechoslovakia]]
* 1925: [[Turin]], Italy
* 1924: [[Luxembourg City]], [[Luxembourg]]
* 1923: [[Kassel]], Germany
* 1922: [[Dessau]], [[Germany]]
* 1921: [[Vienna]], [[Austria]]
{{div col end}}

==See also==
{{Portal|Language|Constructed languages}}
* [[Comparison between Esperanto and Ido]]
* [[Comparison between Ido and Novial]]
* [[Comparison between Ido and Interlingua]]
* [[Interhelpo]]
* [[English false friends in Ido]]
* [[Engelbert Pigal]]

==References==
{{Reflist|20em}}

'''Additional notes'''
# L. Couturat, L. Leau. ''Delegation pour l'adoption d'une Langue auxiliare internationale'' (15–24 October 1907). Coulommiers: Imprimerie Paul Brodard, 1907

==External links==
{{sister project links|auto=1|d=y|commons=Category:Ido|iw=y}}

* [http://idolinguo.org.uk/ The international language Ido]
* [http://www.ido.li/ Union for the International Language Ido] (in Ido)
* [http://en.ido.li/ Ido : a Modern Language]
* [https://idofonduro.org/wp/index.php/en/ The IDO foundation for language research in memory of Hellmut Röhnish]
* [http://interlanguages.net/Hist.html Otto Jespersen's history of Ido]
* [http://interlanguages.net/PAL.html Henry Jacob's history of Ido]
* [http://www.crazyverse.com/ido/ido_for_all.pdf Ido for all – English course for learning Ido]
* [http://www.ido-vivo.info/ Online Ido library] (in Ido)
* [https://tatoeba.org/en/sentences/show_all_in/ido/none/none Examples of Ido Phrases]

{{Constructed languages}}

{{Authority control}}

[[Category:Esperantido]]
[[Category:Ido language| ]]
[[Category:Constructed languages]]
[[Category:International auxiliary languages]]
[[Category:Constructed languages introduced in the 1900s]]
[[Category:International auxiliary languages introduced in the 1900s]]