verb vs imperative verb

verb and imperative verb both are nouns.

Word	Noun	Adjective	Verb	Adverb
verb	Yes	No	No	No
imperative verb	Yes	No	No	No

As nouns, imperative verb is a hyponym of verb; that is, imperative verb is a word with a more specific, narrower meaning than verb:

verb: a content word that denotes an action, occurrence, or state of existence
imperative verb: a verb in the imperative mood.

verb (noun)	imperative verb (noun)
a content word that denotes an action, occurrence, or state of existence	a verb in the imperative mood.
the word class that serves as the predicate of a sentence