imperfect

Universal Words adjective, noun adjective containing faults or mistakes; not complete or perfect: an imperfect world * an imperfect understanding of English * All our sale items are slightly imperfect. imperfectly adverb noun (the imperfect) (also the imperfect tense) [sing.] (grammar) the verb tense that expresses action in the past that is not complete. It is often called the past progressive or past continuous: In 'while I was washing my hair', the verb is in the imperfect.