/ Dictionary / Index C calyptra: Meaning and Definition of Find definitions for: ca•lyp•tra Pronunciation: (ku-lip'tru), [key] — n. Bot. Also calleda hood or hoodlike part, as the lid of the capsule in mosses. a root cap. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: calyptra (Thesaurus) Calypso calyptrogen Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language