/ Dictionary / Index G gearbox: Meaning and Definition of Find definitions for: gear•box Pronunciation: (gēr'boks"), [key] — n. a transmission, as in an automobile. a shield or housing for gears. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: gearbox (Thesaurus) gear gearing Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language