copula vs linking verb

copula and linking verb both are nouns.

Word	Noun	Adjective	Verb	Adverb
copula	Yes	No	No	No
linking verb	Yes	No	No	No

As nouns, copula and linking verb are synonyms defined as:

copula and linking verb: an equating verb (such as `be' or `become') that links the subject with the complement of a sentence

Other synonyms of copula include copulative.

copula (noun)	linking verb (noun)
an equating verb (such as `be' or `become') that links the subject with the complement of a sentence	an equating verb (such as `be' or `become') that links the subject with the complement of a sentence