- cooperator
- ncollaborator, contributor, participant, participator; confederate, conniver, conspirer, conspirator, abettor, accomplice, accessory or Chiefly Law. accessary, partner in crime, Sl. gun moll or moll; helper, aid or aide, attendant, acolyte, deputy, adjutant, coadjutant, coadjutor, coadjutress or coadjutrix, adjunct, adjuvant, adjutator, Obs. adjutor, auxiliary, ancilla, second, man Friday, gal Friday, henchman, right hand, right-hand man, Sl. gofer; partner, ally, comrade, colleague, associate, consociate, socius, yokefellow or yokemate, companion, helpmate, helpmeet, Obs. helpfellow, co-worker, co-aid, co-partner, consort, confrere, sidekick, friend, Chiefly Brit. mate.
A Note on the Style of the synonym finder. 2014.