/ Dictionary / Index W willow herb: Meaning and Definition of Find definitions for: wil'low herb" Pronunciation: [key] any of numerous plants belonging to the genus Epilobium, of the evening primrose family, having terminal clusters of purplish or white flowers. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: willowherb (Thesaurus) willow flycatcher Willowick Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language