/ Dictionary / Index C Cels.: Meaning and Definition of Find definitions for: Cels. Pronunciation: [key] Celsius. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Celotex Celsius Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language