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Webster 1913 Edition
Tautochrone
Tau′to-chrone
,Noun.
[Gr. [GREEK], for [GREEK] [GREEK] the same + [GREEK] time: cf. F.
tautochrone
.] (Math.)
A curved line, such that a heavy body, descending along it by the action of gravity, will always arrive at the lowest point in the same time, wherever in the curve it may begin to fall;
as, an inverted cycloid with its base horizontal is a
. tautochrone