/ Dictionary / Index A absorption spectrum: Meaning and Definition of Find definitions for: absorp'tion spec"trum Pronunciation: [key] — Physics. Physics. the spectrum formed by electromagnetic radiation that has passed through a medium in which radiation of certain frequencies is absorbed. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. absorption nebula absorptive Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language