/ Dictionary / Index M misbehavior: Meaning and Definition of Find definitions for: mis•be•hav•ior Pronunciation: (mis"bi-hāv'yur), [key] — n. improper, inappropriate, or bad behavior. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: misbehavior (Thesaurus) misbehave misbelief Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language