/ Dictionary / Index C cleisto-: Meaning and Definition of Find definitions for: cleisto- Pronunciation: [key] a combining form meaning “closed,” “capable of being closed,” used in the formation of compound words: cleistogamy; cleistothecium. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Cleisthenes cleistocarp Related Content Daily Word Quiz: fresco Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language