Webster's 1913 Dictionary
BRACHYSTOCHRONE
Bra *chys "to *chrone, n. Etym: [Incorrect for brachistochrone, fr. Gr. brachistochrone. ] (Math. )
Defn: 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.
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