/ Dictionary / Index B buck bean: Meaning and Definition of Find definitions for: buck' bean" Pronunciation: [key] a bog plant, Menyanthes trifoliata, of the gentian family, having narrow clusters of white or pink flowers. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: buckbean (Thesaurus) buckaroo buckboard Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language