/ Dictionary / Index C cloud base: Meaning and Definition of Find definitions for: cloud' base" Pronunciation: [key] the apparent lower surface of a cloud or cloud layer. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cloud banner cloudberry Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language