/ Dictionary / Index C coact: Meaning and Definition of Find definitions for: co•act Pronunciation: (kō-akt'), [key] — v.t., v.i. to do or act together. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: coact (Thesaurus) coachwhip coaction Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language