Crossword clues for cissoid
cissoid
The Collaborative International Dictionary
Cissoid \Cis"soid\, n. [Gr. ? like ivy; ? ivy + e'i^dos form.] (Geom.) A curve invented by Diocles, for the purpose of solving two celebrated problems of the higher geometry; viz., to trisect a plane angle, and to construct two geometrical means between two given straight lines.
Wiktionary
n. (context geometry English) Any of a family of curves defined as the locus of a point, ''P'', on a line from a given fixed point and intersecting two given curves, ''C''1 and ''C''2, where the distance along the line from ''C''1 to ''P'' remains constant and equal to the distance from ''P'' to ''C''2.
Wikipedia
In geometry, a cissoid is a curve generated from two given curves C, C and a point O (the pole). Let L be a variable line passing through O and intersecting C at P and C at P. Let P be the point on L so that OP = PP. (There are actually two such points but P is chosen so that P is in the same direction from O as P is from P.) Then the locus of such points P is defined to be the cissoid of the curves C, C relative to O.
Slightly different but essentially equivalent definitions are used by different authors. For example, P may be defined to be the point so that OP = OP + OP. This is equivalent to the other definition if C is replaced by its reflection through O. Or P may be defined as the midpoint of P and P; this produces the curve generated by the previous curve scaled by a factor of 1/2.
The word "cissoid" comes from the Greek kissoeidēs " ivy shaped" from kissos "ivy" and -oeidēs "having the likeness of".
Usage examples of "cissoid".
He hurried after her, down the scree to where You Bastard was lying with his head and neck flat on the ground, flicking his ears in the heat and idly applying You Vicious Brute's Theory of Transient Integrals to a succession of promising cissoid numbers.