/ Dictionary / Index O onager: Meaning and Definition of Find definitions for: on•a•ger Pronunciation: (on'u-jur), [key] — pl. -gri -gers. a wild ass, Equus hemionus, of southwestern Asia. an ancient and medieval military catapult for throwing stones. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: onager (Thesaurus) on-again, off-again onagraceous Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language