/ Dictionary / Index A agst.: Meaning and Definition of Find definitions for: agst. Pronunciation: [key] against. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. A.G.S. Agt. Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language