/ Dictionary / Index A AGC: Meaning and Definition of Find definitions for: AGC Pronunciation: [key] advanced graduate certificate. automatic gain control. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. agba agcy. Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language