Brachystochrone
Brachystochrone ({not transcribed}) , noun
[Incorrect for brachistochrone, from Greek bra`chistos shortest (superl. of brachy`s short) + {not transcribed} time: compare French brachistochrone. ]
(Mathematics) A curve, in which a body, starting from a given point, and descending solely by the force of gravity, will reach another given point in a shorter time than it could by any other path. This curve of quickest descent, as it is sometimes called, is, in a vacuum, the same as the cycloid.