/ Dictionary / Index C coaction: Meaning and Definition of Find definitions for: co•ac•tion Pronunciation: (kō-ak'shun), [key] — n. force or compulsion, either in restraining or in impelling. co•ac•tion Pronunciation: (kō-ak'shun), [key] — n. joint action. any interaction among organisms within a community. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: coaction (Thesaurus) coact coactive Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language