/ Dictionary / Index J jackass: Meaning and Definition of Find definitions for: jack•ass Pronunciation: ( jak'as"), [key] — n. a male donkey. a contemptibly foolish or stupid person; dolt; blockhead; ass. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: jackass (Thesaurus) jackaroo jackass bark Related Content Daily Word Quiz: ablution Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language