Breadcrumb Home > Dictionary > Index X x-ray astronomy: Meaning and Definition of Find definitions for: x'-ray astron"omy Pronunciation: [key] the branch of astronomy that studies celestial objects by means of the x-rays emitted by them. Cf.(def 1b). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. x-ray x-ray burster ✖ Related Content Daily Word Quiz: solecism Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language