imperfective aspect vs imperfective

imperfective aspect and imperfective both are nouns.

Word	Noun	Adjective	Verb	Adverb
imperfective aspect	Yes	No	No	No
imperfective	Yes	No	No	No

As nouns, imperfective aspect and imperfective are synonyms defined as:

imperfective aspect and imperfective: aspect without regard to the beginning or completion of the action of the verb

imperfective aspect (noun)	imperfective (noun)
aspect without regard to the beginning or completion of the action of the verb	aspect without regard to the beginning or completion of the action of the verb