/ Dictionary / Index I internal gear: Meaning and Definition of Find definitions for: inter'nal gear" Pronunciation: [key] — Mach. Mach. a gear having teeth cut on an inner cylindrical surface. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. internal exile internal hemorrhoid Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language