/ Dictionary / Index C cooperativity: Meaning and Definition of Find definitions for: co•op•er•a•tiv•i•ty Pronunciation: (kō-op"ur-u-tiv'i-tē), [key] — n. Biochem. the increase or decrease in the rate of interaction between a reactant and a protein as the reactant concentration increases. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cooperative store Cooper City Related Content Daily Word Quiz: ounterfeit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language