perfective vs perfective aspect

perfective and perfective aspect both are nouns.

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

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

perfective and perfective aspect: the aspect of a verb that expresses a completed action

perfective (noun)	perfective aspect (noun)
the aspect of a verb that expresses a completed action	the aspect of a verb that expresses a completed action
a tense of verbs used in describing action that has been completed (sometimes regarded as perfective aspect)