co-adaptation|kəʊædæpˈteɪʃən| [f. co- + adaptation.] Adaptation of two or more things to each other, mutual adaptation. 1803Month. Mag. XVI. 12 We readily perceive their admirable co-adaptation.1878Darwin Orig.Spec., Hist.Sk.Introd. 17 Numerous and beautiful co-adaptations which we see throughout nature.