Adapta'tion. n.s. [from adapt.] The act of fitting one thing to another; the fitness of one thing to another.
Some species there be of middle natures, that is, of bird and beast, as batts; yet are their parts so set together, that we cannot define the beginning or end of either, there being a commixtion of both, rather than adaptation or cement of the one unto the other. Brown's Vulgar Errours, b. iii. c. ii.
Their adhesion may be in part ascribed, either to some elastical motion in the pressed glass, or to the exquisite adaptation of the almost numberless, though very small, asperities of the one, and the numerous little cavities of the other; whereby the surfaces do lock in with one another, or are, as it were, clasped together. Boyle.