Meaning of cissoid

cis•soid

Pronunciation: (sis'oid), [key]
— n. Geom.
  1. a curve having a cusp at the origin and a point of inflection at infinity. Equation:= 2asin&thgr;tan&thgr;. r
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.