/ Dictionary / Index V valve gear: Meaning and Definition of Find definitions for: valve' gear" Pronunciation: [key] (in a reciprocating engine) the mechanism for opening and closing the valves at certain points in each stroke. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. valved valve-in-head engine Related Content Daily Word Quiz: banshee Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language