—adj.
1 not fully formed or done; faulty, incomplete.
2 Gram. (of a tense) denoting a (usu. past) action in progress but not completed at the time in question (e.g. they were singing).
3 Mus. (of a cadence) ending on the dominant chord.
—n. the imperfect tense.
Phrases and idioms:
imperfect rhyme Prosody a rhyme that only partly satisfies the usual criteria (e.g. love and move).
Derivatives:
imperfectly adv.
Etymology: ME imparfit etc. f. OF imparfait f. L imperfectus (as IN-(1), PERFECT)
Useful english dictionary. 2012.