Word Study
conchoid
CIDE DICTIONARY
conchoid, n. [Gr. ; shell + e'i^dos form: cf. F. conchoïde.].
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. [1913 Webster]
ROGET THESAURUS
conchoid
Curvature
N curvature, curvity, curvation, incurvature, incurvity, incurvation, bend, flexure, flexion, flection, conflexure, crook, hook, bought, bending, deflection, deflexion, inflection, inflexion, concameration, arcuation, devexity, turn, deviation, detour, sweep, curl, curling, bough, recurvity, recurvation, sinuosity, kink, carve, arc, arch, arcade, vault, bow, crescent, half-moon, lunule, horseshoe, loop, crane neck, parabola, hyperbola, helix, spiral, catenary, festoon, conchoid, cardioid, caustic, tracery, arched ceiling, arched roof, bay window, bow window, sine curve, spline, spline curve, spline function, obliquity, curved, curviform, curvilineal, curvilinear, devex, devious, recurved, recurvous, crump, bowed, vaulted, hooked, falciform, falcated, semicircular, crescentic, sinusoid, parabolic, paraboloid, luniform, lunular, semilunar, conchoidal, helical, double helical, spiral, kinky, cordiform, cordated, cardioid, heart shaped, bell shaped, boat shaped, crescent shaped, lens shaped, moon shaped, oar shaped, shield shaped, sickle shaped, tongue shaped, pear shaped, fig shaped, kidney-shaped, reniform, lentiform, lenticular, bow-legged, oblique, circular, aduncated, arclike, arcuate, arched, beaked, bicorn, bicornuous, bicornute, clypeate, clypeiform, cymbiform, embowed, galeiform, hamate, hamiform, hamous, hooked, linguiform, lingulate, lobiform, lunate, navicular, peltate, remiform, rhamphoid, rostrate, rostriferous, rostroid, scutate, scaphoid, uncate, unguiculate, unguiform.For further exploring for "conchoid" in Webster Dictionary Online