D defs.my
Entry 1 sense Webster, 1913

Coöperate

· Co·öp·er·ate · IPA
01 v. i. To act or operate jointly with another or others; to concur in action, effort, or effect.
imp. & p. p. Cooperated; p. pr. & vb. n. Cooperating
  1. 1.
    To act or operate jointly with another or others; to concur in action, effort, or effect.
    “Whate'er cooperates to the common mirth.” — Crashaw.