/ Dictionary / Index C cosmotron: Meaning and Definition of Find definitions for: cos•mo•tron Pronunciation: (kos'mu-tron"), [key] — n. Physics. a proton accelerator. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: cosmotron (Thesaurus) cosmos cosponsor Related Content Daily Word Quiz: arid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language