/ Dictionary / Index C contagium: Meaning and Definition of Find definitions for: con•ta•gium Pronunciation: (kun-tā'jum, -jē-um), [key] — pl. -gia the causative agent of a contagious or infectious disease, as a virus. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. contagious magic contain Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language