/ Dictionary / Index T tappet: Meaning and Definition of Find definitions for: tap•pet Pronunciation: (tap'it), [key] — n. Mach. a sliding rod, intermittently struck by a cam, for moving another part, as a valve. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: tappet (Thesaurus) tapper tapping Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language