Adjective
of or relating to a copula
Source: WordNeta copular verb Source: Internet
A copula is often a verb or a verb-like word, though this is not universally the case. citation A verb that is a copula is sometimes called a copulative or copular verb. Source: Internet
Additional uses of copular verbs A copular verb may also have other uses supplementary to or distinct from its uses as a copula. Source: Internet
Adjectives that come after copular verbs are predicate adjectives, and nouns that come after linking verbs are predicate nouns. Source: Internet
In some analyses, they are viewed as a form of verbal takeover by a copular strategy. Source: Internet
The auxiliary functions of these verbs derive from their copular function, and can be interpreted as a special case of the copular function (the verbal form that follows it being considered adjectival). Source: Internet