/ Dictionary / Index P prolonged-action: Meaning and Definition of Find definitions for: pro•longed-ac•tion Pronunciation: (pru-lôngd'ak'shun, -longd'-), [key] — adj. Pharm. sustained-release. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. prolonge prolonge knot Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language