cooperation UK /kəʊˌɒp.əˈɹeɪ.ʃən/US /koʊˌɑ.pəˈɹeɪ.ʃən/ noun3 •willing help from a person or group in doing something, often by sharing space, time or thingsSouth Korea is seeking cooperation from China to produce artificial rain to help fight increasing pollution. — 2019 •The act of cooperating. •Association for mutual benefit, such as for purposes of production or purchase. formscooperations