# cissoid

## English[edit]

### Etymology[edit]

From Ancient Greek *κισσός* (kissós, “ivy”) + *εἶδος* (eîdos, “form, image”).

### Noun[edit]

**cissoid** (*plural* **cissoids**)

- (geometry) 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}.*The***cissoid**of a circle and a line is a conchoid

#### Related terms[edit]

#### Translations[edit]

*Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for cissoid in* Webster’s Revised Unabridged Dictionary

*, G. & C. Merriam, 1913.)*