/ Dictionary / Index C cellmate: Meaning and Definition of Find definitions for: cell•mate Pronunciation: (sel'māt"), [key] — n. a fellow inmate in a prison cell. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cell line cell-mediated immunity Related Content Daily Word Quiz: hedonist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language