Eth

Eth (/ɛð/ edh, uppercase: ⟨Ð⟩, lowercase: ⟨ð⟩; also spelled edh or eð), known as ðæt in Old English, is a letter used in Old English, Middle English, Icelandic, Faroese (in which it is called edd), and Elfdalian.

It was also used in Scandinavia during the Middle Ages, but was subsequently replaced with ⟨dh⟩, and later ⟨d⟩.

It is often transliterated as ⟨d⟩.

The lowercase version has been adopted to represent a voiced dental fricative (IPA: [ð]) in the International Phonetic Alphabet.

In Faroese, ⟨ð⟩ is not assigned to any particular phoneme and appears mostly for etymological reasons, but it indicates most glides. When ⟨ð⟩ appears before ⟨r⟩, it is in a few words pronounced [ɡ]. In the Faroese alphabet, ⟨ð⟩ follows ⟨d⟩.

⟨Ð⟩ is sometimes used in Khmer romanization to represent ឍ thô.

In Icelandic, ⟨ð⟩, called "eð", represents an alveolar non-sibilant fricative, voiced [ð̠] intervocalically and word-finally, and voiceless [θ̠] otherwise, which form one phoneme, /θ/. Generally, /θ/ is represented by thorn ⟨Þ⟩ at the beginning of words and by ⟨ð⟩ elsewhere. The ⟨ð⟩ in the name of the letter is devoiced in the nominative and accusative cases: [ɛθ̠]. In the Icelandic alphabet, ⟨ð⟩ follows ⟨d⟩.

In Olav Jakobsen Høyem's version of Nynorsk based on Trøndersk, ⟨ð⟩ was always silent, and was introduced for etymological reasons.

In Old English, ⟨ð⟩ (called ðæt) was used interchangeably with ⟨þ⟩ to represent the Old English dental fricative phoneme /θ/ or its allophone [ð], which exist in modern English as the voiceless and voiced dental fricatives both now spelled ⟨th⟩.

Unlike the runic letter ⟨þ⟩, ⟨ð⟩ is a modified Roman letter. Neither ⟨ð⟩ nor ⟨þ⟩ was found in the earliest records of Old English. A study of Mercian royal diplomas found that ⟨ð⟩ began to emerge in the early 8th century, with ⟨ð⟩ becoming strongly preferred by the 780s. Another source indicates that the letter is "derived from Irish writing".

Under the reign of King Alfred the Great, ⟨þ⟩ grew greatly in popularity and started to overtake ⟨ð⟩, and did so completely by the Middle English period. ⟨þ⟩ in turn went obsolete by the Early Modern English period, mostly due to the rise of the printing press, and was replaced by the digraph ⟨th⟩.

⟨Ð⟩ has also been used by some in written Welsh to represent /ð/, which is normally represented as ⟨dd⟩.

• /ð/ (U+00F0) represents a voiced dental fricative in the International Phonetic Alphabet.
• /ᶞ/ (U+1D9E) is used in phonetic transcription.
• ᴆ (U+1D06) is used in the Uralic Phonetic Alphabet.

Upper and lower case forms of eth have Unicode encodings:

• U+00D0 Ð LATIN CAPITAL LETTER ETH (Ð)
• U+00F0 ð LATIN SMALL LETTER ETH (ð)

These Unicode codepoints were inherited from ISO/IEC 8859-1 ("ISO Latin-1") encoding.

• A capital eth is used as the currency symbol for Dogecoin, a cryptocurrency.

• African D – Variant of the Latin letter D used in African alphabets
• D
• D with stroke – Variant of the letter D, used in Sámi alphabets, Serbo-Croatian Latin alphabet, and Vietnamese
• Insular script – Medieval writing system common to Ireland and England
• T
• Thorn – Letter of Old English and some Scandinavian languages

• Ladefoged, Peter; Maddieson, Ian (1996). The Sounds of the World's Languages. Oxford: Blackwell. ISBN 0-631-19815-6.
• Pétursson, Magnus (1971), "Étude de la réalisation des consonnes islandaises þ, ð, s, dans la prononciation d'un sujet islandais à partir de la radiocinématographie" [Study of the realisation of Icelandic consonants þ, ð, s, in the pronunciation of an Icelandic subject from radiocinematography], Phonetica, 33 (4): 203–216, doi:10.1159/000259344, S2CID 145316121

• "Thorn and eth: how to get them right", Operinan, Briem, archived from the original on 2019-07-26, retrieved 2010-08-22
• "Älvdalsk ortografi", Förslag till en enhetlig stavning för älvdalska (PDF) (in Swedish), February 2007, archived from the original (PDF) on 6 February 2007.