D

D (named dee /ˈdiː/) is the fourth letter of the modern English alphabet and the ISO basic Latin alphabet.

The Semitic letter Dāleth may have developed from the logogram for a fish or a door. There are many different Egyptian hieroglyphs that might have inspired this. In Semitic, Ancient Greek and Latin, the letter represented /d/; in the Etruscan alphabet the letter was superfluous but still retained (see letter B). The equivalent Greek letter is Delta, Δ.

The minuscule (lower-case) form of 'd' consists of a loop and a tall vertical stroke. It developed by gradual variations on the majuscule (capital) form. 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.

In most languages that use the Latin alphabet, and in the International Phonetic Alphabet, ⟨d⟩ generally represents the voiced alveolar or voiced dental plosive /d/. However, in the Vietnamese alphabet, it represents the sound /z/ in northern dialects or /j/ in southern dialects. (See D with stroke and Dz (digraph).) In Fijian it represents a prenasalized stop /nd/. In some languages where voiceless unaspirated stops contrast with voiceless aspirated stops, ⟨d⟩ represents an unaspirated /t/, while ⟨t⟩ represents an aspirated /tʰ/. Examples of such languages include Icelandic, Scottish Gaelic, Navajo and the Pinyin transliteration of Mandarin.

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