pluperfect tense vs past perfect tense

pluperfect tense and past perfect tense both are nouns.

Word	Noun	Adjective	Verb	Adverb
pluperfect tense	Yes	No	No	No
past perfect tense	Yes	No	No	No

As nouns, pluperfect tense and past perfect tense are synonyms defined as:

pluperfect tense and past perfect tense: a perfective tense used to express action completed in the past

Other synonyms of pluperfect tense include past perfect, pluperfect.

pluperfect tense (noun)	past perfect tense (noun)
a perfective tense used to express action completed in the past	a perfective tense used to express action completed in the past