Al-

(, also transliterated as el- and in some cases il- and ul-) is a  prefix in the Arabic language which functions as a definite article, comparable to the English word . However, al- never stands as a word by itself, but is always joined to the beginning of the word it modifies — for example, 'the book' is al-kitāb, which is written . Like the English word 'the', al- is not a permanent component of words it is attached to; it is only prefixed to a word to make the word definite — continuing the example, 'a book', or simply 'book', is kitāb, which is written , as Arabic does not have an indefinite article. Unlike English usage, Arabic grammar  requires al- to be used with adjectives modifying the definite noun. For example, 'the big book' in English requires only one instance of 'the', but in Arabic the phrase is al-kitāb al-kabīr, written , with two instances of al- (DEF-book-DEF-big, literally, 'the book the big'). Hebrew, another language in the Semitic family, has similar rules for the use of its definite article.
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(A prefix.)
To; at; on; -- in OF. shortened to a-. See Ad-.
  

(A prefix.)
The Arabic definite article answering to the English the; as, Alkoran, the Koran or the Book; alchemy, the chemistry.
  

(A prefix.)
All; wholly; completely; as, almighty, almost.