comb. form of Gr. βράχιστος, superl. of βραχύς short, as in ǁ Brachistocephali, men or races with the shortest skull; Brachistocephaly, the quality of having the shortest type of skull. Cf. BRACHYCEPHALIC. Also Brachistochrone [Gr. χρόν-ος time], the curve in which a body descending to a given point under the action of gravity will perform its journey in the shortest possible time; the curve of quickest descent.
1866. Huxley, Preh. Rem. Caithn., 85. Sub-divide the Brachycephali into Eurycephali … and Brachistocephali. Ibid., 111. Of these, but one reaches the limits of brachistocephaly.
a. 1774. Goldsm., Surv. Exp. Philos. (1776), I. 153. The curve of a cycloid, which was afterwards called by the hard name of a Brachystochrone, or the line of quickest descent.
1877. E. C. Thomas, trans. Lange’s Materialism, I. 122. The falling body reaches the goal more quickly upon the brachystochrone than upon an inclined plane.
