TROCHOID

trochoid. Trochoid, n. another name for the cycloid

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Tro″choid (?), n. [[Gr. � a wheel + -oid; cf. F. trochoïde. See Troche.]] (Geom.) The curve described by any point in a wheel rolling on a line; a cycloid; a roulette; in general, the curve described by any point fixedly connected with a moving curve while the moving curve rolls without slipping on a second fixed curve, the curves all being in one plane. Cycloids, epicycloids, hypocycloids, cardioids, etc., are all trochoids.