The Collaborative International Dictionary
Conchoid \Con"choid\, n. [Gr. ?; ? shell + e'i^dos form: cf. F. concho["i]de.] (Geom.) 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.
Wiktionary
n. 1 (context mathematics geometry English) Any of a family of curves defined as the locus of points ''p'', such that each ''p'' is on a line that passes through a given fixed point ''P'' and intersects a given curve, ''C'', and the distance from ''p'' to the point of intersection with ''C'' is a specified constant (note that for nontrivial cases two such points ''p'' satisfy the criteria, and the resultant curve has two parts). 2 (context geology English) A conchoidal fracture in rock.
Wikipedia
Conchoid can refer to:
- Conchoid curve, an equation discovered by the mathematician Nicomedes
- Conchoidal fracture, a breakage pattern characteristic to certain glasses and crystals
A conchoid is a curve derived from a fixed point O, another curve, and a length d.
Usage examples of "conchoid".
Eliza had sat next to him and pronounced their names: the Limaçon of Pascal, the Kampyle of Eudoxus, the Conchoid of de Sluze, the Quadratrix of Hippias, the Epitrochoid, Tractrix, and the Cassinian Ovals.