Conchoid
Pronunciation : Con"choid
Part of Speech : n.
Etymology : [Gr. concho?de.] (Geom.)
Definition : Defn: A curve, of the fourth degree, first made use of by the Greek geometer, Nicomedes, who invented it for the purpose of trisecting an angle and duplicating the cube.
Source : Webster's Unabridged Dictionary, 1913