In Arabic, an article or inseparable prefix, answering to the Italian il, and the Sp. el and la. Its use is to render nouns definite, like the English the; as, Alkoran, the Koran, or the Book, by eminence; alcove, alchemy, alembic, almanac, &c.
In English, sometimes a contraction of the A.-S. æthel, noble or illustrious; but more generally, a contraction of ald or alt, old (A.-S. eald, Ger. alt, old); prefixed to many names, as Alburg.
A form of the Latin prefix ad, used in composition before l, for ease of pronunciation; as, allude from alludere, for adluere.