/ Dictionary / Index I improper: Meaning and Definition of Find definitions for: im•prop•er Pronunciation: (im-prop'ur), [key] — adj. not proper; not strictly belonging, applicable, correct, etc.; erroneous: He drew improper conclusions from the scant evidence. not in accordance with propriety of behavior, manners, etc.: improper conduct at a funeral. unsuitable or inappropriate, as for the purpose or occasion: improper attire for a formal dance. abnormal or irregular: improper functioning of the speech mechanism. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: improper (Thesaurus) impromptu improper fraction Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language