Locus /(?)/

Lo·cus

Locus

n.

pl. Loci, Loca

  1. A place; a locality.
  2. The line traced by a point which varies its position according to some determinate law; the surface described by a point or line that moves according to a given law. (Math.)

Phrases & Compounds
Plane locus
a locus that is a straight line, or a circle.
Solid locus
a locus that is one of the conic sections.