Definite Article:  

A word that designates or specifies a particular substantive. The definite article (the) is a special category of adjective that derives from the demonstrative_pronoun (this/that, these/those) and thus has demonstrative force in pointing out a particular person, place, or thing (the home, the books, the sheep). The definite article can also have generic force when used with singular substantives to indicate a whole class (the bishop, meaning all bishops).