Al- (Arabic: ٱلْـ, also romanized as el-, il-, and l- as pronounced in some varieties of Arabic), is the definite article in the Arabic language: a particle (ḥarf) whose function is to render the noun on which it is prefixed definite. For example, the word كتاب kitāb "book" can be made definite by prefixing it with al-, resulting in الكتاب al-kitāb "the book". Consequently, al- is typically translated as "the" in English.
Unlike most other Arabic particles, al- is always prefixed to another word and never stands alone. Consequently, many dictionaries do not list it, and it is almost invariably ignored in collation, as it is not an intrinsic part of the word.