brachisto-comb. form of Gr. βράχιστος, superl. of βραχύς short, as in ‖ brachistocephali|bræˌkɪstəʊˈsɛfəlaɪ|, men or races with the shortest skull; brachistocephaly|-ˈsɛfəlɪ|, the quality of having the shortest type of skull. Cf. brachycephalic. Also brachistochrone|bræˈkɪstəkrəʊn|[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.1866Huxley Preh. Rem. Caithn. 85 Sub-divide the Brachycephali into Eurycephali..and Brachistocephali.Ibid. 111 Of these, but one reaches the limits of brachistocephaly.a1774Goldsm.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.1877E. Thomas tr.Lange's Materialism I. 122 The falling body reaches the goal more quickly upon the brachystochrone than upon an inclined plane.