/ Dictionary / Index M MGy Sgt: Meaning and Definition of Find definitions for: MGy Sgt Pronunciation: [key] master gunnery sergeant. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mgt. MH Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language