cooperator
1. [ noun ] an associate who works with others toward a common goal
Synonyms: partner pardner collaborator
Examples:

"partners in crime"

Related terms: associate bridge_partner copartner dancing_partner silent_partner partner
Similar spelling:   cooperate
  cooperative
  cooperation
  copartner
  couverture
  Couvertier
  copyreader
  cooperatively
  covertly
  copyread
  Coverdale
  copartnership
  cofferdam