Work in concert

• Worth with
• Work together, as organisms
• Do in tandem
• Work in tandem
• Perform as one

Wiktionary Word definitions in Wiktionary
Etymology 1 (context obsolete English) forced, constrained, done under compulsion. v (context obsolete English) To compel, constrain, force. Etymology 2 vb. (context rare English) To work together.

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Coact \Co*act"\, v. t. [L. coactare, intens. fr. cogere, coactum, to force. See Cogent .] To force; to compel; to drive. [Obs.] The faith and service of Christ ought to be voluntary and not coacted. --Foxe.

WordNet Word definitions in WordNet
v. act together, as of organisms