/ Dictionary / Index R rad: Meaning and Definition of Find definitions for: rad Pronunciation: (rad), [key] — n. Physics. a unit of absorbed dose equal to 0.01 Gy. Cf.(def. 4a). rad Pronunciation: (rad), [key] — n. radical. —adj. fine; wonderful. rad Pronunciation: [key] — Math. Math. radian; radians. rad. Pronunciation: [key] — Math. Math. radical. radix. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rad (Thesaurus) racy radar Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language