mood vs imperative form

mood and imperative form both are nouns.

Word	Noun	Adjective	Verb	Adverb
mood	Yes	No	No	No
imperative form	Yes	No	No	No

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

mood: verb inflections that express how the action or state is conceived by the speaker
imperative form: a mood that expresses an intention to influence the listener's behavior

mood (noun)	imperative form (noun)
a characteristic (habitual or relatively temporary) state of feeling	a mood that expresses an intention to influence the listener's behavior
verb inflections that express how the action or state is conceived by the speaker
the prevailing psychological state