Serving to complete or accomplish something; having the quality of bringing something to completion or fulfillment.
From accomple (archaic form) or Latin completus 'filled up' + -ive suffix. It's a rare adjective form related to accomplish and completion.
This is a word that's barely alive in English—you might find it in very old texts or specialized philosophical writing, but it shows how we constantly experiment with word forms before settling on what actually survives.
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