/ Dictionary / Index B Benadryl: Meaning and Definition of Find definitions for: Ben•a•dryl Pronunciation: (ben'u-dril), [key] — Pharm., Trademark. Pharm.,Trademark. a brand of diphenhydramine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: benadryl (Thesaurus) ben bename Related Content Daily Word Quiz: pundit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language