/ Thesaurus / R Synonyms of radioactive decay Find synonyms for: Noun1. decay, radioactive decay, disintegration, nuclear reactionusage: the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiationWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: dormant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language