Learn how to say Pluperfect correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word pluperfect:
(of a tense) denoting an action completed prior to some past point of time specified or implied, formed in English by had and the past participle, as in he had gone by then.
the pluperfect tense.
late 15th century: from modern Latin plusperfectum, from Latin (tempus praeteritum) plus quam perfectum ‘(past tense) more than perfect’