One of the forms, or the inflections or changes of form, of a noun, pronoun, or adjective, which indicate its relation to other words, and in the aggregate constitute its declension; the relation which a noun or pronoun sustains to some other word.
Case shows the grammatical relation of inflected forms such as nouns and pronouns to other words (nominative, possessive, objective cases).
a form of a noun (and any agreeing adjective) that indicates by its ending how the word functions grammatically in the sentence. Latin has six cases (see individual definitions): nominative, genitive, dative, accusative, ablative, and vocative. English has only two cases: nominative (used for the subject of a sentence) and objective (used for everything else).