/ Dictionary / Index C cyathium: Meaning and Definition of Find definitions for: cy•ath•i•um Pronunciation: (sī-ath'ē-um), [key] — pl. -ath•i•a an inflorescence consisting of a cup-shaped involucre enclosing an apetalous, pistillate flower surrounded by several staminate flowers. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cyathiform cyathus Related Content Daily Word Quiz: agitated Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language