/ Dictionary / Index X x-ray tube: Meaning and Definition of Find definitions for: x'-ray tube" Pronunciation: [key] an electronic tube for producing x-rays, essentially a cathode-ray tube in which a metal target is bombarded with high-energy electrons. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. x-ray therapy XS Related Content Daily Word Quiz: diligent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language