Æ is a grapheme 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 many languages. As a letter of the Old English alphabet it was called æsc ‘ash tree’ after the Anglo-Saxon Futhorc rune which it transliterated; its traditional name in English is still ash (pronounced ).
In English, usage of the ligature varies in different places. In modern typography, and where technological limitations prevent (such as in use of computers and typewriters), æ is often eschewed for the digraph ae. This is often considered incorrect, especially when rendering foreign words where æ is properly a letter (e.g. Æsir, Ærø) or brand names which make use of the ligature (e.g. Æon Flux, Encyclopædia Britannica). In the United States, the problem of the ligature is sidestepped in many cases by use of a simplified spelling with "e"; compare U.S. medieval with traditional British mediæval. However, given the long history of such spellings, they are sometimes used to invoke archaism or in literal quotations of historic sources, for words such as encyclopædia or dæmon.
In Old English, the a–e ligature was used to denote a sound intermediate between those of a and e (IPA ), very much like the short a of cat in many dialects of modern English.
In Classical Latin, the combination AE denotes a diphthong (IPA ) that had a value similar to the long i in most dialects of modern English. It was used both in native words (spelled with ai before the 2nd century BC) and in borrowings from Greek words having the diphthong αι (alpha iota). 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 a simple long vowel (IPA ) in late Latin. In some medieval scripts, the ligature was simplified to , the letter e with a tail hanging to the left, e-caudata. This form further simplified into a plain e, which may have influenced or been influenced by the pronunciation change.
In the modern French alphabet, it is used to spell Latin borrowings like et cætera, tænia, ex æquo.
In Faroese it represents the ligature of the so-called long æ (IPA ), whereas the short æ is a simple . It's etymological origin is Old Norse é, and this is particularly evident in the dialects of Suðuroy, where Æ is long and [ɛ short:
In Icelandic, the aesc signifies a diphthong (IPA ). In Danish and Norwegian, æ represents a simple vowel, namely IPA and , respectively. In the South Danish dialect, as well as in several Norwegian dialects, the phoneme Æ has a significant meaning, "I", and is thus a normal spoken word. In some Southern-Jutish dialects Æ is also the definite article: 'Æ hus' (The house). These dialects are rarely committed to writing. The same phoneme is represented in Finnish and Swedish by the letter ä, and in German by a-umlaut (ä).
The Ossetic language used the letter æ when it was written using the Latin script (1923–38). Since then, Ossetian has used a Cyrillic alphabet with an identical-looking letter ().
For computers, when using the Latin-1 or Unicode character sets, the code points for Æ and æ are U+00C6 and U+00E6, respectively, or 198 and 230 in decimal. The characters can be entered by holding the Alt key while typing in 0198 or 0230 on the number pad on Windows systems (the Alt key and the letters' corresponding 8-bit ASCII codes, 145 for æ and 146 for Æ, also work), or by holding down the option key whilst typing an apostrophe ( ' ) on a Macintosh system under various keyboard layouts, including the U.S. layout.
There is also Cyrillic ' and ' in Unicode (U+04D4, U+04D5), though in practice the Latin letters Æ and æ (U+00C6, U+00E6) are used in Cyrillic texts (such as on Ossetian sites in the Internet).
In HTML, the HTML character entity references Æ and æ have been assigned to Æ and æ, respectively, where “lig” stands for ligature.
The progressive metal band Tool used an Æ for the title of their third album, Ænima, and the song Ænema from that album. This is similar to the usage of the heavy metal umlaut, but is meant as a combination of anima and enema.
Uncommon Latin letters | Phonetic transcription symbols | Danish language | Norwegian language | Icelandic language | Faroese language | Old English language | Vowel letters
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