/ Dictionary / Index I internal revenue: Meaning and Definition of Find definitions for: inter'nal rev'enue Pronunciation: [key] the revenue of a government from any domestic source, usually considered to be any source other than customs. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. internal resistance Internal Revenue Service Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language