View source for D

{{Short description|Fourth letter of the Latin alphabet}}
{{About|the letter of the alphabet}}
{{Technical reasons|D#|D-sharp|D♯ (disambiguation)}}
{{Technical reasons|:D|the keyboard symbol|List of emoticons}}
{{pp-semi|small=yes}}
{{pp-move|small=yes}}
{{Infobox grapheme
| name = D
| letter = D d
| variations = 
| script = [[Latin script]]
| type = [[Alphabet]]
| typedesc = ic
| language = [[Latin language]]
| phonemes = {{flex list|[{{IPAlink|d}}]|[{{IPAlink|t}}]|[{{IPAlink|d͡ʒ}}]|[{{IPAlink|ɗ}}]|[{{IPAlink|z}}~[[Vietnamese phonology#Comparison of initials|j]]]|[{{IPAlink|ⁿ|ⁿd}}]|[{{IPAlink|ɖ}}]|[{{IPAlink|ɾ}}]|[{{IPAlink|ð}}~{{IPAlink|ð̞}}~[[Danish phonology#Consonants|ð̠˕ˠ]]]|{{IPAc-en|d|iː}}}}
| unicode = U+0044, U+0064
| alphanumber = 4
| number = 4; 500
| fam1 = <hiero>K1</hiero><hiero>K2</hiero><hiero>O31</hiero>
| fam2 = [[Image:Proto-semiticD-02.svg|class=skin-invert-image|20px|Dalet]]
| fam3 = [[File:PhoenicianD-01.svg|class=skin-invert-image|20px|Early Phoenician Dalet]]
| fam4 = [[Image:Phoenician daleth.svg|class=skin-invert-image|20px|Dalet]]
| fam5 = [[Delta (letter)|Δ δ]]
| fam6 = [[𐌃]]
| usageperiod = {{circa}} 700 BCE to present
| children = {{flex list|[[Ď]]|[[ǅ]]|[[ǲ]]|[[Đ]]|[[Ð]]|[[Ƌ]]|[[Ꭰ]]|[[₫]]|[[∂]]}}
| sisters = {{flex list|[[Д]]|[[Dalet|<span>ד</span> | <span>د</span> | <span>ܕ</span>]]|[[wikt:Դ|Դ]]|[[wikt:դ|դ]]|[[Ꭰ]]|[[Ꮫ]]|[[ደ]]}}
| equivalents = 
| associates = [[List of Latin-script digraphs#D|d(x)]]
| direction = Left-to-right
| image = Latin_letter_D.svg
| imageclass = skin-invert-image
}}
{{Latin letter info|d}}

'''D''', or '''d''', is the fourth [[Letter (alphabet)|letter]] of the [[Latin alphabet]], used in the [[English alphabet|modern English alphabet]], the alphabets of other western European languages and others worldwide. Its name in English is [[English alphabet#Letter names|''dee'']] (pronounced {{IPAc-en|'|d|iː|audio=LL-Q1860 (eng)-Flame, not lame-D.wav}}), plural ''dees''.<ref>"D" ''Oxford English Dictionary,'' 2nd edition (1989); ''[[Merriam-Webster]]'s Third New International Dictionary of the English Language, Unabridged'' (1993); "dee", ''op. cit.''</ref>

==History==
{| class="wikitable"
|- style="background-color:#EEEEEE; text-align:center;"
! Egyptian hieroglyph <br>door, fish
! Phoenician <br/>[[dalet]]h
! Western Greek<br/>[[Delta (letter)|Delta]]
! Etruscan <br/>D
! Latin <br/>D
|- style="background-color:white; background-color:light-dark(white,black); text-align:center;"
|<hiero>O31</hiero><hiero>K1</hiero><hiero>K2</hiero>
| [[File:PhoenicianD-01.svg|class=skin-invert-image|frameless|35x35px]]
| [[File:Greek Delta 04.svg|class=skin-invert-image|50px]]
| [[File:EtruscanD-01.svg|class=skin-invert-image|30px]]
| [[File:Capitalis monumentalis D.svg|class=skin-invert-image|x30px|Latin D]]
|}

The [[Semitic languages|Semitic]] letter [[Daleth|Dāleth]] may have developed from the [[logogram]] for a fish or a door.<ref>{{Cite web|title=The letter D|url=https://issuu.com/kenwilsonmax/docs/chicken__health_issue/s/25385|access-date=2021-07-06|website=issuu|archive-date=2021-08-29|archive-url=https://web.archive.org/web/20210829194452/https://issuu.com/kenwilsonmax/docs/chicken__health_issue/s/25385|url-status=dead}}</ref> There are many different [[Egyptian hieroglyph]]s that might have inspired this. In Semitic, [[Ancient Greek]]<ref name=":0">{{Cite web |title=Definition of DELTA |url=https://www.merriam-webster.com/dictionary/delta |access-date=2022-05-03 |website=www.merriam-webster.com |language=en}}</ref> and [[Latin]],<ref>{{Cite web |title=Latin Alphabet |url=https://www.sfu.ca/~ramccall/AncientandmodernLatinalphabet.pdf |archive-url=https://web.archive.org/web/20101226155729/http://www.sfu.ca/~ramccall/AncientandmodernLatinalphabet.pdf |archive-date=2010-12-26 |url-status=live}}</ref> the letter represented {{IPA|/d/}}; in the [[Etruscan alphabet]]<ref>Rex Wallace (2008) 𐌆𐌉𐌙 𐌓𐌀𐌔𐌍𐌀 ''𐌀 Zikh Rasna: A Manual of the Etruscan Language and Inscriptions''</ref> the letter was archaic but still retained. The equivalent [[Greek letter]] is delta, [[Delta (letter)|Δ]].<ref name=":0" />

The [[lower case|minuscule]] (lower-case) form of 'd' consists of a lower-story left [[Typeface anatomy#Strokes|bowl]] and a [[Typeface anatomy#Strokes|stem ascender]]. It most likely developed by gradual variations on the [[upper case|majuscule]] (capital) form 'D', and is now composed as a stem with a full [[Typeface anatomy#Strokes|lobe]] to the right. In handwriting, it was common to start the arc to the left of the vertical stroke, resulting in a [[serif]] at the top of the arc. This serif was extended while the rest of the letter was reduced, resulting in an angled stroke and loop. The angled stroke slowly developed into a vertical stroke.<ref>{{Cite web |title=Introduction to Old English |url=https://lrc.la.utexas.edu/eieol/engol |access-date=2022-05-03 |website=The Linguistics Research Center}}</ref>

==Use in writing systems==
{| class="wikitable mw-collapsible"
|+ Pronunciation of {{angbr|d}} by language
! Orthography
! Phonemes
|-
! {{nwr|[[Standard Chinese]]}} ([[Pinyin]])
| {{IPAslink|t}}
|-
! [[Dungan alphabets#Latin|Dungan]]
| {{IPAslink|d̥}}
|-
! [[English orthography|English]]
| {{IPAslink|d}}
|-
! [[French orthography|French]]
| {{IPAslink|d}}, silent
|-
! [[German orthography|German]]
| {{IPAslink|d}}, {{IPAslink|t}}
|-
![[Icelandic language|Icelandic]]
|{{IPAslink|t}}
|-
! rowspan="2" | [[Portuguese orthography|Portuguese]] 
| {{IPAslink|d}}
|-
|{{IPAblink|d͡ʒ}}, allophone of {{IPAslink|d}} before {{IPAslink|i}}, {{IPAslink|ĩ}} and {{IPAslink|j}} in some Brazilian dialects
|-
! [[Spanish orthography|Spanish]]
| {{IPAslink|d}}
|-
! [[Turkish orthography|Turkish]]
| {{IPAslink|d}}
|-
! [[Vietnamese alphabet|Vietnamese]]
| {{IPAslink|z}}, {{IPAslink|j}}
|}

===English===
In [[English orthography|English]], {{angbr|d}} generally represents the [[voiced alveolar plosive]] {{IPA|/d/}}.

The letter {{angbr|d}} is the [[letter frequency|tenth most frequently used]] in the English language.

===Other languages===
[[File:Boundary stone on the Demeljoch - 2.jpg|thumb|The letter D, standing for "Deutschland" ([[German language|German]] for "[[Germany]]"), on a [[boundary stone]] at the border between Austria and Germany.]] 
In most languages that use the Latin alphabet, {{angbr|d}} generally represents the [[voiced alveolar plosive|voiced alveolar]] or [[voiced dental plosive]] {{IPA|/d/}}.

In the [[Vietnamese alphabet]], it represents the sound {{IPA|/z/}} in northern dialects or {{IPA|/j/}} in southern dialects. In [[Fijian language|Fijian]], it represents a [[prenasalized consonant|prenasalized]] stop {{IPA|/ⁿd/}}.<ref>{{Cite book |title=Pacific languages: an introduction |first=John |last=Lynch |page=97 |url=https://books.google.com/books?id=zYfV1jN3whUC&q=d+fijian+prenasalized&pg=PA97 |year=1998 |publisher=[[University of Hawaii Press]] |isbn=0-8248-1898-9 }}</ref>

In some languages where [[voice (phonetics)|voice]]less [[aspiration (phonetics)|unaspirated]] stops contrast with voiceless aspirated stops, {{angbr|d}} represents an unaspirated {{IPA|/t/}}, while {{angbr|t}} represents an aspirated {{IPA|/tʰ/}}. Examples of such languages include [[Icelandic language|Icelandic]], [[Scottish Gaelic]], [[Navajo language|Navajo]] and the [[pinyin]] transliteration of [[Standard Chinese|Mandarin]].

===Other systems===
In the [[International Phonetic Alphabet]], {{angbr|d}} represents the [[voiced alveolar plosive]] {{IPA|/d/}}.

==Other uses==
{{Main article|D (disambiguation)}}
* In the [[hexadecimal]] (base 16) numbering system, D is a number that corresponds to the number 13 in [[decimal]] (base 10) counting.<ref>{{Cite web |title=Hexadecimal Number System {{!}} There are Many Ways to Write Numbers |url=https://u.osu.edu/storageofdata/hexadecimal-number-system/ |access-date=2022-05-20 |website=u.osu.edu}}</ref>
* The [[Roman numeral]] D represents the number [[500 (number)|500]].<ref>{{cite book | url=https://archive.org/details/illustratedintro0000gord | url-access=registration | quote=roman numerals. | title=Illustrated Introduction to Latin Epigraphy | publisher=[[University of California Press]] | date=1983 | access-date=3 October 2015 | author=Gordon, Arthur E. | pages=[https://archive.org/details/illustratedintro0000gord/page/44 44]| isbn=9780520038981 }}</ref>
* [[Unit prefix]] d, meaning one tenth.
* D is the grade below C but above E/F in the [[Grading (education)|school grading system]].
* D is the [[international vehicle registration code]] for [[Germany]] (also [[.de]] as its [[top-level domain]]).
* In [[Cantonese]]: Because the lack of Unicode CJK support in early computer systems, many Hong Kongers and Singaporeans used the capitalized D to represent {{lang-zh|c=[[wikt:啲|啲]]|j=di1|l=a little|labels=no|out=c}}.<ref>{{Cite web |date=March 23, 2011 |title=The Roman Alphabet in Cantonese |url=https://languagelog.ldc.upenn.edu/nll/?p=3045 |access-date=13 September 2023 |website=[[University of Pennsylvania]]}}</ref>
* In the [[Biblical manuscript#Gregory-Aland|Gregory-Aland system]] for cataloging Biblical manuscripts, D can refer to documents in the [[Western text-type]] tradition, either [[Codex Bezae]] or [[Codex Claromontanus]].
* d. is the standard abbreviation for the [[Penny (British pre-decimal coin)]] (from {{langx|la|[[denarius]]}})

==Related characters==
<!-- Please only list characters (symbols in a writing system, but not just convenience code points in Unicode) that are actually related in terms of origin to the letter that is the topic of this article. Characters that merely look subjectively similar need not apply. See https://en.wikipedia.org/wiki/Wikipedia:Verifiability and https://en.wikipedia.org/wiki/Wikipedia:Identifying_reliable_sources before adding more. -->

===Descendants and related characters in the Latin alphabet===
* Ɖ ɖ : [[African D]]
* Ð ð : [[Ð|Latin letter Eth]]
* D with [[diacritic]]s: [[D with stroke|Đ đ]] [[Tau gallicum|Ꟈ ꟈ]]<ref name="L219179">{{Cite web|url=https://www.unicode.org/L2/L2019/19179-n5044-tau-gallicum.pdf |archive-url=https://web.archive.org/web/20190613190943/http://www.unicode.org/L2/L2019/19179-n5044-tau-gallicum.pdf |archive-date=2019-06-13 |url-status=live|title=L2/19-179: Proposal for the addition of four Latin characters for Gaulish|date=2019-05-26|first1=Michael|last1=Everson|first2=Chris|last2=Lilley}}</ref> [[Ɗ|Ɗ ɗ]] [[Dot (diacritic)|Ḋ ḋ]] [[Ḍ|Ḍ ḍ]] [[Ḑ|Ḑ ḑ]] [[Circumflex|Ḓ ḓ]] [[Ď|Ď ď]] [[Macron below|Ḏ ḏ]]
* Phonetic symbols related to D:
** Symbols related to D used in the [[International Phonetic Alphabet|IPA]]: {{IPA link|ɖ}} {{IPA link|ɗ}}
** Symbols related to D used in the [[Uralic Phonetic Alphabet]]: {{not a typo|ᴅ ᴰ ᵈ}}<ref>{{Cite web|url=https://www.unicode.org/L2/L2002/02141-n2419-uralic-phonetic.pdf |archive-url=https://web.archive.org/web/20130819185337/http://www.unicode.org/L2/L2002/02141-n2419-uralic-phonetic.pdf |archive-date=2013-08-19 |url-status=live|title=L2/02-141: Uralic Phonetic Alphabet characters for the UCS|date=2002-03-20|first1=Michael|last1=Everson|author-link1=Michael Everson|display-authors=etal}}</ref>
** [[International Phonetic Alphabet#Superscript IPA|Superscript IPA letters]]: 𐞋 𐞌 𐞍<ref>{{Cite web|title=L2/20-252R: Unicode request for IPA modifier-letters (a), pulmonic|url=https://www.unicode.org/L2/L2020/20252r-mod-ipa-a.pdf |archive-url=https://web.archive.org/web/20210730010133/https://www.unicode.org/L2/L2020/20252r-mod-ipa-a.pdf |archive-date=2021-07-30 |url-status=live|date=2020-11-08|first1=Kirk|last1=Miller|first2=Michael|last2=Ashby}}</ref>
** Other phonetic symbols related to D: [[ȡ]]<ref>{{Cite web|url=https://www.unicode.org/L2/L2001/01347-n2366r.pdf |archive-url=https://web.archive.org/web/20130819124737/http://www.unicode.org/L2/L2001/01347-n2366r.pdf |archive-date=2013-08-19 |url-status=live|title=L2/01-347: Proposal to add six phonetic characters to the UCS|date=2001-09-20|first1=Richard|last1=Cook|first2=Michael|last2=Everson}}</ref> [[ᵭ]]<ref>{{Cite web|url=https://www.unicode.org/L2/L2003/03174r2-mid-tilde.pdf |archive-url=https://web.archive.org/web/20130819204725/http://www.unicode.org/L2/L2003/03174r2-mid-tilde.pdf |archive-date=2013-08-19 |url-status=live|title=L2/03-174R2: Proposal to Encode Phonetic Symbols with Middle Tilde in the UCS|date=2003-09-30|first=Peter|last=Constable}}</ref> [[ᶁ]]<ref name="L204132">{{Cite web|url=https://www.unicode.org/L2/L2004/04132-n2740-phonetic.pdf |archive-url=https://web.archive.org/web/20130819114855/http://www.unicode.org/L2/L2004/04132-n2740-phonetic.pdf |archive-date=2013-08-19 |url-status=live|title=L2/04-132 Proposal to add additional phonetic characters to the UCS|date=2004-04-19|first=Peter|last=Constable}}</ref> [[D with hook and tail|ᶑ]]<ref name="L204132"/>
* Ƌ ƌ : [[Ƌ|D with topbar]]
* 𝼥: D with mid-height left hook – Used by the [[British and Foreign Bible Society]] in the early 20th century for [[romanization]] of the [[Malayalam]] language.<ref>{{Cite web|title=L2/21-156: Unicode request for legacy Malayalam|url=https://www.unicode.org/L2/L2021/21156-legacy-malayalam.pdf |archive-url=https://web.archive.org/web/20210907191404/https://www.unicode.org/L2/L2021/21156-legacy-malayalam.pdf |archive-date=2021-09-07 |url-status=live|date=2021-07-16|first1=Kirk|last1=Miller|first2=Neil|last2=Rees}}</ref>
* Ꝺ ꝺ: [[Insular script|Insular]] D is used in various phonetic contexts<ref>{{Cite web|url=https://www.unicode.org/L2/L2006/06266-n3122-insular.pdf |archive-url=https://web.archive.org/web/20130819182322/http://www.unicode.org/L2/L2006/06266-n3122-insular.pdf |archive-date=2013-08-19 |url-status=live|title=L2/06-266: Proposal to add Latin letters and a Greek symbol to the UCS|date=2006-08-06|first=Michael|last=Everson}}</ref>

===Ancestors and siblings in other alphabets===
* 𐤃: [[Phoenician alphabet|Semitic]] letter [[Dalet]], from which the following symbols originally derive:
** Δ δ: [[Greek alphabet|Greek]] letter [[Delta (letter)|Delta]], from which the following symbols originally derive:
*** {{Script|Copt|Ⲇ ⲇ}}: [[Coptic alphabet|Coptic]] letter Delta
*** Д д: [[Cyrillic]] letter [[De (Cyrillic)|De]]
*** 𐌃: [[Old Italic script|Old Italic]] D, the ancestor of modern Latin D
**** {{Script|Runr|ᛞ}}: [[Runes|Runic]] letter [[dagaz]], which is possibly a descendant of Old Italic D
**** {{Script|Runr|ᚦ}}: Runic letter [[thurisaz]], another possible descendant of Old Italic D
*** {{Script|Goth|𐌳}}: [[Gothic alphabet|Gothic]] letter daaz, which derives from Greek Delta

===Derived signs, symbols and abbreviations===
* ₫: [[Vietnamese đồng|Đồng sign]]
* ⅆ: Unicode symbol for d used as derivative symbol
* ∂: [[∂|the partial derivative symbol]], <math>\partial</math>

==Other representations==
===Computing <span class="anchor" id="Computing codes"></span>===
The Latin letters {{angbr|D}} and {{angbr|d}} have [[Unicode]] encodings {{unichar|0044}} and {{unichar|0064}}. These are the same [[code point]]s as those used in [[ASCII]] and [[ISO 8859]]. There are also [[precomposed character]] encodings for {{angbr|D}} and {{angbr|d}} with diacritics, for most of those listed [[#Related characters|above]]; the remainder are produced using [[combining diacritic]]s.

Variant forms of the letter have unique code points for specialist use: the [[Mathematical Alphanumeric Symbols|alphanumeric symbols set]] in mathematics and science, [[plosive]] sounds in linguistics and [[halfwidth and fullwidth forms]] for legacy [[CJK characters|CJK]] font compatibility.

===Other===
{{Letter other reps
|NATO=Delta
|Morse=–··
|Character=D4
|Braille=⠙
|fingerspelling=D
}}
In [[British Sign Language]] (BSL), the letter 'd' is indicated by signing with the right hand held with the index and thumb extended and slightly curved, and the tip of the thumb and finger held against the extended index of the left hand.

{{clear}}

==References==
{{Reflist}}

==External links==
{{Commons}}
*{{Wiktionary-inline|D}}
*{{Wiktionary-inline|d}}

{{Latin script|D|}}

[[Category:ISO basic Latin letters]]