View source for Royal Thai General System of Transcription

{{distinguish|Real-time gross settlement}}
{{Short description|Thai romanization system}}
{{Contains special characters|Thai}}
{{Cleanup|reason=inconsistent year of publishing/introduction|date=May 2024}}
{{Infobox romanization
| engvar    = gb
| name      = Royal Thai General System of Transcription
| altname   = RTGS
| type      =  
| languages = [[Thai language|Thai]]
| creator   = [[Royal Institute of Thailand]]
| date      = 1932
| time      = current
| romanised-from = [[Thai script]]
}}
The '''Royal Thai General System of Transcription''' ('''RTGS''') is the official<ref name = "announcement">{{citation|journal=Royal Gazette|volume=116|issue=37 ง|pages=11|script-title=th:ประกาศสำนักนายกรัฐมนตรี เรื่อง หลักเกณฑ์การถอดอักษรไทยเป็นอักษรโรมันแบบถ่ายเสียง|url=http://www.ratchakitcha.soc.go.th/DATA/PDF/2542/D/037/11.PDF|archive-url=https://web.archive.org/web/20120127154113/http://www.ratchakitcha.soc.go.th/DATA/PDF/2542/D/037/11.PDF|url-status=dead|archive-date=January 27, 2012|date=1999-05-11|language=th}}</ref><ref>{{citation|url=http://www.eki.ee/wgrs/rom1_th.pdf|title=Report on the Current Status of United Nations Romanization Systems for Geographical Names: Thai}}</ref> system for rendering [[Thai language|Thai]] words in the [[Latin alphabet]]. It was published by the [[Royal Institute of Thailand]] in early 1917, when Thailand was called [[Siam]].<ref name=exposition_Thai>{{citation|url=https://www.orst.go.th/pdfjs/web/viewer.html?file=/FILEROOM/CABROYINWEB/DRAWER004/GENERAL/DATA0000/00000763.PDF|title=Standard for transcribing the Thai alphabet into the Roman alphabet by conveying the sound|language=th}}</ref><ref>{{citation|url=http://unstats.un.org/unsd/geoinfo/UNGEGN/docs/8th-uncsgn-docs/inf/8th_UNCSGN_econf.94_INF.41.pdf|title=Principles of Romanization for Thai Script by Transcription Method}} (UN document)</ref>

It is used in road signs<ref>{{citation|url=http://www.ooh5.go.th/book/CA/CA01.pdf|at=Appendix ง|language=th|title=Handbook and standard for traffic signs|access-date=2017-11-15|archive-date=2017-11-15|archive-url=https://web.archive.org/web/20171115222340/http://www.ooh5.go.th/book/CA/CA01.pdf|url-status=dead}}</ref><ref>{{citation|url=https://nstda.or.th/archives/ชื่อบ้านนามเมือง/|language=th|title=geographical names|date=7 August 2021 }}</ref> and government publications and is the closest method to a standard of [[transcription (linguistics)|transcription]] for Thai, but its use, even by the government, is inconsistent. The system is almost identical to the one that is defined by [[ISO 11940-2]].

==Features==
Prominent features of the system are:
*It uses only unmodified letters from the [[Latin alphabet]] without [[diacritic]]s.
*It spells all [[vowel]]s and [[diphthong]]s with vowel letters: {{angbr|a}}, {{angbr|e}}, {{angbr|i}}, {{angbr|o}}, {{angbr|u}}.
**Single letters {{angbr|a}}, {{angbr|e}}, {{angbr|i}}, {{angbr|o}}, {{angbr|u}} are [[monophthongs]] (simple vowels), with the same value as in the [[International Phonetic Alphabet]] (IPA).
** [[Digraph (orthography)|Digraph]]s with trailing {{angbr|e}} are monophthongs; {{angbr|[[ae (digraph)|ae]]}}, {{angbr|[[oe (digraph)|oe]]}}, {{angbr|[[ue (digraph)|ue]]}} sound like {{IPA|/ɛ, ɤ, ɯ/}} respectively.
**Digraphs and [[trigraph (orthography)|trigraph]]s with trailing {{angbr|a}}, {{angbr|i}}, {{angbr|o}} are [[diphthongs]] and indicate IPA {{IPA|/a, j, w/}} respectively.
* It uses [[consonant]]s as in IPA except as follows:
**Digraphs with {{angbr|h}} ({{angbr|[[ph (digraph)|ph]]}}, {{angbr|[[th (digraph)|th]]}}, {{angbr|[[kh (digraph)|kh]]}}) are [[aspiration (phonetics)|aspirated]] {{IPA|/pʰ, tʰ, kʰ/}} consonants to distinguish them from unaspirated {{angbr|p}}, {{angbr|t}}, {{angbr|k}}.
**It uses {{angbr|[[ng (digraph)|ng]]}} for {{IPA|/ŋ/}}, as in English.
**It uses {{angbr|[[ch (digraph)|ch]]}} for {{IPA|/tɕʰ/}} and {{IPA|/tɕ/}}, somewhat like English.
**It uses {{angbr|y}} for {{IPA|/j/}}, as in English.

Final consonants are transcribed according to pronunciation, not [[Thai orthography]].

Vowels are transcribed in the position in the word where they are pronounced, not as in Thai orthography. Implied vowels, which are not written in Thai orthography, are transcribed as pronounced.

A hyphen is used to avoid ambiguity in syllable separation before a succeeding syllable that starts with a vowel and before {{angbr|ng}} if the preceding syllable ends with a vowel.

Transcribed words are written with spaces between them although there are [[scriptio continua|no space]]s in Thai. For example, {{Lang|th|สถาบันไทยคดีศึกษา}} ''Institute of Thai Studies'' is transcribed as {{Lang|th-Latn|Sathaban Thai Khadi Sueksa}}. However, [[compound (linguistics)|compound]]s and names of persons are written without spaces between words. For example, {{Lang|th|ลูกเสือ}} (from {{Lang|th|ลูก}} + {{Lang|th|เสือ}}, ''scout'') is transcribed as {{Lang|th-th|luksuea}}, not {{Lang|th-Latn|luk suea}}, and {{Lang|th|โชคชัย จิตงาม}}, the first and last names of a person, is transcribed as {{Lang|th-Latn|Chokchai Chitngam}}, not {{Lang|th-Latn|Chok Chai Chit Ngam}}.<ref name = "announcement"/>

==Transcription table==
For consonants, the transcriptions are given for both initial and final position in the syllable. For vowels, a dash ("&ndash;") indicates the relative position of the vowel's initial consonant.

{|
! Consonants || &nbsp; || Vowels
|-
|
<!-- Consonants -->
{| class="wikitable"
! Letter || Initial position || Final position
|-
| {{lang|th|ก}} || k || k
|-
| {{lang|th|ข}} {{lang|th|ฃ}} {{lang|th|ค}} {{lang|th|ฅ}} {{lang|th|ฆ}} || kh || k
|-
| {{lang|th|ง}} || ng || ng
|-
| {{lang|th|จ}} || ch || t
|-
| {{lang|th|ฉ}} {{lang|th|ช}} || ch || t
|-
| {{lang|th|ซ}} || s || t
|-
| {{lang|th|ฌ}} || ch || -
|-
| {{lang|th|ญ}} || y || n
|-
| {{lang|th|ฎ}} || d || t
|-
| {{lang|th|ฏ}} || t || t
|-
| {{lang|th|ฐ}} {{lang|th|ฑ}} {{lang|th|ฒ}} || th || t
|-
| {{lang|th|ณ}} || n || n
|-
| {{lang|th|ด}} || d || t
|-
| {{lang|th|ต}} || t || t
|-
| {{lang|th|ถ}} {{lang|th|ท}} {{lang|th|ธ}} || th || t
|-
| {{lang|th|น}} || n || n
|-
| {{lang|th|บ}} || b || p
|-
| {{lang|th|ป}} || p || p
|-
| {{lang|th|ผ}} || ph || -
|-
| {{lang|th|ฝ}} || f || -
|-
| {{lang|th|พ}} || ph || p
|-
| {{lang|th|ฟ}} || f || p
|-
| {{lang|th|ภ}} || ph || p
|-
| {{lang|th|ม}} || m || m
|-
| {{lang|th|ย}} || y || -
|-
| {{lang|th|ร}} || r || n
|-
| {{lang|th|ฤ}} || rue, ri, roe || -
|-
| {{lang|th|ฤๅ}} || rue || -
|-
| {{lang|th|ล}} || l || n
|-
| {{lang|th|ฦ}} || lue || -
|-
| {{lang|th|ฦๅ}} || lue || -
|-
| {{lang|th|ว}} || w || -
|-
| {{lang|th|ศ}} || s || t
|-
| {{lang|th|ษ}} || s || t
|-
| {{lang|th|ส}} || s || t
|-
| {{lang|th|ห}} || h || -
|-
| {{lang|th|ฬ}} || l || n
|-
| {{lang|th|ฮ}} || h || -
|}
| &nbsp;&nbsp;&nbsp;&nbsp;
| valign="top"|
<!-- Vowels-->
{| class="wikitable"
! Letter || Romanization
|-
| {{lang|th|–ะ}}, {{lang|th|–ั}}, {{lang|th|รร}} (with final), {{lang|th|–า}} || a
|-
| {{lang|th|รร}} (without final) || an
|-
| {{lang|th|–ำ}} || am
|-
| {{lang|th|–ิ}}, {{lang|th|–ี}} || i
|-
| {{lang|th|–ึ}}, {{lang|th|–ื}}, —{{lang|th|ือ}} || ue
|-
| {{lang|th|–ุ}}, {{lang|th|–ู}} || u
|-
| {{lang|th|เ–ะ}}, {{lang|th|เ–็}}, {{lang|th|เ–}} || e
|-
| {{lang|th|แ–ะ}}, {{lang|th|แ–}} || ae
|-
| {{lang|th|โ–ะ}}, {{lang|th|–}}, {{lang|th|โ–}}, {{lang|th|เ–าะ}}, {{lang|th|–อ}} || o
|-
| {{lang|th|เ–อะ}}, {{lang|th|เ–ิ}}, {{lang|th|เ–อ}} || oe
|-
| {{lang|th|เ–ียะ}}, {{lang|th|เ–ีย}} || ia
|-
| {{lang|th|เ–ือะ}}, {{lang|th|เ–ือ}} || uea
|-
| {{lang|th|–ัวะ}}, {{lang|th|–ัว}}, {{lang|th|–ว–}} || ua
|-
| {{lang|th|ใ–}}, {{lang|th|ไ–}}, {{lang|th|–ัย}}, {{lang|th|ไ–ย}}, {{lang|th|–าย}} || ai
|-
| {{lang|th|เ–า}}, {{lang|th|–าว}} || ao
|-
| {{lang|th|–ุย}} || ui
|-
| {{lang|th|โ–ย}}, {{lang|th|–อย}} || oi
|-
| {{lang|th|เ–ย}} || oei
|-
| {{lang|th|เ–ือย}} || ueai
|-
| {{lang|th|–วย}} || uai
|-
| {{lang|th|–ิว}} || io
|-
| {{lang|th|เ–็ว}}, {{lang|th|เ–ว}} || eo
|-
| {{lang|th|แ–็ว}}, {{lang|th|แ–ว}} || aeo
|-
| {{lang|th|เ–ียว}} || iao
|}
|}

==History==
There have been four versions of the RTGS, those promulgated in 1932, 1939, 1968 and 1999. The general system was issued by the [[Ministry of Education (Thailand)|Ministry of Public Instruction]] in 1932, and subsequent issues have been issued by the Royal Institute of Thailand.

===Table of changes===
{| class="wikitable" style=text-align:center
! rowspan="2" | Letter
! colspan="4" | Initial position
! colspan="4" | Final position
|-
! 1932
! 1939
! 1968
! 1999
! 1932
! 1939
! 1968
! 1999
|-
| {{lang|th|จ}} || č || čh || ch || ch || colspan="4" | t
|-
| {{lang|th|ฤ}} || rư || rư || ru || rue || colspan="4" | -
|-
| {{lang|th|ฤ}} || rơ || rœ || roe || roe || colspan="4" | -
|-
| {{lang|th|ฤๅ}} || rư || rư || ru || rue || colspan="4" | -
|-
| {{lang|th|ฦ}} || lư || lư || lu || lue || colspan="4" | -
|-
| {{lang|th|ฦๅ}} || lư || lư || lu || lue || colspan="4" | -
|}

{| class="wikitable" style=text-align:center
! rowspan="2" | Letter
! colspan="4" | Romanization
|-
! 1932
! 1939
! 1968
! 1999
|-
|  {{lang|th|–ึ}}, {{lang|th|–ื}} || ư || ư || u || ue
|-
|  {{lang|th|แ–ะ}}, {{lang|th|แ–}} || e̩ || æ || ae || ae
|-
|  {{lang|th|เ–าะ}}, {{lang|th|–อ}} || o̦ || ǫ || o || o
|-
|  {{lang|th|เ–อะ}}, {{lang|th|เ–ิ}}, {{lang|th|เ–อ}} || ơ || œ || oe || oe
|-
|  {{lang|th|เ–ือะ}}, {{lang|th|เ–ือ}} || ưa || ưa || ua || uea
|-
|  {{lang|th|–อย}} || o̦i || ǫi || oi || oi
|-
|  {{lang|th|เ–ย}} || ơi || œi || oei || oei
|-
|  {{lang|th|เ–ือย}} || ưai || ưai || uai || ueai
|-
|  {{lang|th|–ิว}} || iu || iu || iu || io
|-
|  {{lang|th|แ–็ว}}, {{lang|th|แ–ว}} || e̩o || æo || aeo || aeo
|-
|  {{lang|th|เ–ียว}} || iau || ieo || ieo || iao
|}

===1932 version===
The general system was set up by a committee of the [[Ministry of Education (Thailand)|Ministry of Public Instruction]] on the following principles:<ref name="RTGS_1939">{{Citation|date=March 1941|title = A Notification of the Royal Institute concerning the Transcription of Thai Characters into the Roman|journal = The Journal of the Thailand Research Society|volume = XXXIII|pages = 49–65|url=http://www.siamese-heritage.org/jsspdf/1941/JSS_033_1d_RoyalInstituteTranscriptionOfThaiIntoRomanCharacters.pdf
| access-date = 20 September 2012
}}</ref>
# The general system should be expandable to the precise system.
# The general system should be based on pronunciation, and one sound should be represented by one symbol or letter.
# The general system should be in consonance with the principles of Thai grammar, orthography, and pronunciation.
# In selecting symbols or letters, account should be taken of existing types for printing and typewriting and of existing systems of transcription.

The committee considered that for the general system, tone and quantity marks were unneeded. They would be provided for the precise system.<ref name="RTGS_1939"/> The marks are accents above the vowels,<ref name="RTGS_1939"/> one reason that the vowel symbols used to have no marks above them.<ref name="Griswold_1960"/>

===1939 version===
The 1939 issue allowed short vowels to be marked with a [[breve]] (˘) where expedient.<ref name="RTGS_1939"/> By contrast, the [[ALA-LC]] [https://www.loc.gov/catdir/cpso/romanization/thai.pdf transliteration] uses the 1939 version with the addition of a [[macron (diacritic)|macron]] (¯) for long vowels and a [[rough breathing|spiritus asper]] (ʽ) to transliterate อ {{IPA|/ʔ/}} as a consonant.

The changes in vowel notation copied existing usage (æ, œ)<ref>{{citation
| author = Vajiravudh
| year = 1913
| title = The Romanisation of Siamese Words.
| journal = Journal of the Siam Society
| volume = 9
| issue = 4
| access-date = 2012-07-06
| url = http://www.siamese-heritage.org/jsspdf/1911/JSS_009_4b_KingVajiravudh_RomanisationOfSiameseWords.pdf
}}</ref>
and [[History of the IPA|IPA notation]] (æ, ǫ).<ref name="RTGS_1939"/>

===Relationship to precise system===
The precise system was issued along with the general system in 1939. A transliteration in the precise system could be converted to the general system by doing the following:<ref name="RTGS_1939"/>
# Removing parenthesised character
# Replacing ''ʽ'' and ''hʽ'' by ''h''
# Removing length and tone markings
# Removing ''ḥ'', which corresponds to ะ {{IPA|/ʔ/}}, which may be viewed as a length mark
# Removing the character distinguishing dots below and primes
# Changing ''ay'' and ''aiy'' to ''ai'' except before vowels
# Changing ''č'' to ''čh''
# Changing ''ie'' to ''ia'', ''uo'' to ''ua'' and ''ưœ'' to ''ưa''

The last set of changes removes a graphic distinction between vowels in closed syllables and vowels in open syllables.<ref name="RTGS_1939"/>

The ''h'' is added to ''č'' in the general system to make it easier to read. When the diacritic was subsequently removed, the ''h'' was justified as avoiding the misreading of the transliteration as {{IPA|/k/}} or {{IPA|/s/}} rather than the correct {{IPA|/tɕ/}}.<ref name="exposition_Thai"/>

===1968 version===
The 1968 version removed diacritics, including the horn of ''ư'' and replaced the ligatures ''æ'' and ''œ'' by ''ae'' and ''oe''. While that is more suitable as the standard transliteration for maps, it removed the contrast between the transcriptions of {{lang|th|จ}} {{IPA|/tɕ/}} and {{lang|th|ช}} {{IPA|/tɕʰ/}}, {{lang|th|อึ}} {{IPA|/ɯ/}} and {{lang|th|อุ}} {{IPA|/u/}}, {{lang|th|เอือ}} {{IPA|/ɯa/}} and {{lang|th|อัว}} {{IPA|/ua/}}, and {{lang|th|โอ}} {{IPA|/oː/}} and {{lang|th|ออ}} {{IPA|/ɔː/}}.<ref name="exposition_Thai"/>

===1999 version===
The 1999 version restored the distinction between the transcriptions of the pairs อึ {{IPA|/ɯ/}} and อุ {{IPA|/u/}} and เอือ {{IPA|/ɯa/}} and อัว {{IPA|/ua/}}.<ref name="exposition_Thai"/> It also simplified the transliteration of final ว {{IPA|/w/}}, which now is always transcribed <o>.<ref name="exposition_Thai"/>

===Allowed variants===
The following variants have been allowed:
{| class="wikitable" style=text-align:center
|-
! Preferred form
|čh || æ || œ || ǫ || ơ || ư
|-
! Alternative
|ĉh<ref name="RTGS_1939"/> || ae<ref name="Griswold_1960">{{Citation |title=Afterthoughts on the Romanization of Siamese |date=June 1960 |journal=[[Journal of the Siam Society]] |volume=XLVIII |pages=29–68 |url=https://thesiamsociety.org/wp-content/uploads/1960/03/JSS_048_1c_Griswold_AfterthoughtsOnRomanizationOfSiamese.pdf |access-date=}}</ref>|| oe<ref name="Griswold_1960"/> || o̦<ref name="RTGS_1939"/> || oʼ<ref name="RTGS_1939"/> || uʼ<ref name="RTGS_1939"/>
|}

==Criticism==
The system does not transcribe all features of [[Thai phonology]]. Particularly it has the following shortcomings:
* It does not record [[tone (linguistics)|tone]]s.
* It does not differentiate between [[vowel length|short and long vowels]].
* The notation {{angbr|ch}} does not differentiate between [[International Phonetic Alphabet|IPA]] {{IPA|/tɕ/}} and IPA {{IPA|/tɕʰ/}} (see table below). Using {{angbr|c}} for {{IPA|/tɕ/}} would have been more consistent<ref>{{citation|url=http://www.arts.chula.ac.th/~ling/tts/principles_eng.pdf|title=Principles of Romanization for Thai Script by Transcription Method}} (English version)</ref> with the other stops and is used as such in [[ISO 11940-2]].
* The notation {{angbr|o}} does not differentiate between IPA {{IPA|/ɔ/}} and IPA {{IPA|/o/}} (see table below).

{| class="wikitable"
!&nbsp;
! colspan="4" |Phoneme 1 !! colspan="4" |Phoneme 2
|-
! RTGS
! Thai!!IPA!!Description!!English
! Thai!!IPA!!Description!!English
|-
| ch
| {{lang|th|จ}}
| {{IPA link|tɕ}}
| [[voiceless alveo-palatal affricate|alveo-palatal<br />affricate]]
| roughly like {{angbr|ty}} in "let you"<br />{{citation needed|date=October 2012}}
| {{lang|th|ฉ}}, {{lang|th|ช}}, {{lang|th|ฌ}}
| {{IPA link|tɕʰ}}
| aspirated alveo-<br />palatal affricate
| roughly like {{angbr|ch}} in "check"
|-
| rowspan="2" |o
| {{lang|th|โ–ะ}}, {{lang|th|–}}
| {{IPA|oʔ}}
| close-mid back<br />short rounded
| like the vowel in "note" <br />(American pronunciation)
| {{lang|th|เ–าะ}}
| {{IPA|ɔʔ}}
| open-mid back<br />short rounded
| like {{angbr|o}} in "boy"
|-
| {{lang|th|โ–}}
| {{IPA link|oː}}
| close-mid back<br />long rounded
| like {{angbr|o}} in "go" ''(Scottish English)''
| {{lang|th|–อ}}
| {{IPA link|ɔː}}
| open-mid back<br />long rounded
| like {{angbr|aw}} in "raw"
|}

The [[#1932 Version|original design]] envisioned the general system to give broad details of pronunciation, and the precise system to supplement that with vowel lengths, tones, and specific Thai characters used.<ref name="RTGS_1939"/> The ambiguity of {{angbr|ch}} and {{angbr|o}} was introduced in the [[#1968 Version|1968 version]].

==See also==
* [[ISO 11940]]
* [[ISO 11940-2]]
* [[Thai transliteration]]

==References==
{{reflist|30em}}

==Sources==
{{refbegin}}
*{{Citation |author=Nitaya Kanchanawan |url=http://legacy.orst.go.th/wp-content/uploads/royin-ebook/276/FileUpload/758_6484.pdf |title=Romanization, Transliteration, and Transcription for the Globalization of the Thai Language |journal=The Journal of the Royal Institute of Thailand |volume=31 |number=3 |date=July–September 2006}}<!--Old URL archived at http://web.archive.org/web/20110701000000*/http://www.royin.go.th/upload/276/FileUpload/758_6484.pdf-->
{{refend}}

==External links==
* [https://www.cs.cmu.edu/~ananlada/ThaiRomanizeCOCOSDA99.doc Discussion of romanisation] (Microsoft Word document)
* [http://www.arts.chula.ac.th/%7Eling/tts/ Downloadable Windows-based transcription tool]
* [[ALA-LC]]: [https://www.loc.gov/catdir/cpso/romanization/thai.pdf PDF guide to romanization of Thai (U.S. library of Congress)]

{{DEFAULTSORT:Royal Thai General System Of Transcription}}
[[Category:1932 establishments in Siam]]
[[Category:Romanization of Thai]]
[[Category:Culture of Thailand]]
[[Category:Royal Society of Thailand]]