tautochrone
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- (hình học) đẳng thời // đường đẳng thời
Định nghĩa tiếng Anh
n. A curved line, such that a heavy body, descending\n along it by the action of gravity, will always arrive at the lowest\n point in the same time, wherever in the curve it may begin to fall; as,\n an inverted cycloid with its base horizontal is a tautochrone.