Eth

Eth (/ɛð/, uppercase: Ð, lowercase: ð; also spelled edh or eð) 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 (and d- is rarely used as a mnemonic). The lowercase version has been adopted to represent a voiced dental fricative in the International Phonetic Alphabet.

In Old English, ð (called ðæt by the Anglo-Saxons) was used interchangeably with þ to represent the Old English dental fricative phoneme /θ/, which exists in modern English phonology as the voiced and voiceless dental fricatives now spelled 'th'.

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