/ Dictionary / Index P pinfire: Meaning and Definition of Find definitions for: pin•fire Pronunciation: (pin'fīr"), [key] — adj. of or pertaining to a cartridge fitted with a pin that, when struck by the hammer of the firearm, causes the cartridge to explode. of or pertaining to a firearm that uses such a cartridge. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pinfeather pinfish Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language