/ Dictionary / Index G gear ratio: Meaning and Definition of Find definitions for: gear' ra"tio Pronunciation: [key] — Mach. Mach. the ratio of the rotational speeds of the first and final gears in a train of gears or of any two meshing gears. the ratio of the diameters of the pitch surfaces of any two meshing gears or of the numbers of their teeth. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. gear pump gearset Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language