/ Dictionary / Index P percussion lock: Meaning and Definition of Find definitions for: percus'sion lock" Pronunciation: [key] a gunlock on a firearm that fires by striking a percussion cap. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. percussionist percussion welding Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language