/ Dictionary / Index G grease gun: Meaning and Definition of Find definitions for: grease' gun" Pronunciation: [key] a hand-operated pump for greasing bearings under pressure. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. grease cup grease monkey Related Content Daily Word Quiz: odious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language