Æ

Æ (minuscule: æ) is a grapheme named æsc or ash, formed from the letters a and e, originally a ligature representing a Latin diphthong. It has been promoted to the full status of a letter in the alphabets of some languages, including Norwegian, Danish, Icelandic, and Faroese. As a letter of the Old English Latin alphabet, it was called æsc ("ash tree") after the Anglo-Saxon futhorc rune ᚫ () which it transliterated; its traditional name in English is still ash /æʃ/. It was also used in Old Swedish before being changed to ä. Variants include Ǣ ǣ Ǽ ǽ.

In Classical Latin, the combination AE denotes the diphthong [ai̯], which had a value similar to the long i in fine as pronounced in most dialects of Modern English. Both classical and present practice is to write the letters separately, but the ligature was used in medieval and early modern writings, in part because æ was reduced to the simple vowel [ɛ] during the Roman Empire. In some medieval scripts, the ligature was simplified to ę, an e with ogonek, the e caudata. That was further simplified into a plain e, which may have influenced or been influenced by the pronunciation change. However, the ligature is still relatively common in liturgical books and musical scores. An example is the Motu Propio Ingravescentem Ætatem.

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