Declensable

Declensable is an adjective used in linguistics to describe words that can be inflected to indicate grammatical case. Case refers to the grammatical function of a noun, pronoun, or adjective in a sentence. For example, in Latin, nouns change their endings to show whether they are the subject of a verb (nominative case), the direct object (accusative case), the possessor (genitive case), or the indirect object (dative case). Words that undergo these changes are called declensable.

Many languages, including German, Russian, and ancient Greek, have robust case systems and therefore feature a large number of declensable words. In contrast, English has largely lost its case system. While some pronouns, like "I" and "me," "he" and "him," still show distinctions based on case, most nouns and adjectives in English are not declensable. The concept of declension is primarily associated with inflectional languages, where word endings are modified to convey grammatical information. Adjectives that modify declensable nouns are also often declensable themselves, agreeing with the noun in case, number, and gender. The opposite of declensable is indeclinable, which refers to words that do not change their form to indicate case.