/ Dictionary / Index P propyl group: Meaning and Definition of Find definitions for: pro'pyl group" Pronunciation: [key] — Chem. Chem. any of two univalent, isomeric groups having the formula CH−. Also calledCf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. propylene group propylhexedrine Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language