/ Dictionary / Index P propionic: Meaning and Definition of Find definitions for: pro•pi•on•ic Pronunciation: (prō"pē-on'ik, -ō'nik), [key] — adj. Chem. of or derived from propionic acid. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. propionibacterium propionic acid Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language