In geom., a curve by means of which right lines equal to the circumferences of circles or other curves, and their various parts, may be found mechanically.

About 420 B. C. Hippias of Elis invented a certain curve called the quadratrix by means of which he could square the circle and trisect any angle. "The Teaching of Geometry", David Eugene Smith

About 420 B. C. Hippias of Elis invented a certain curve called the quadratrix by means of which he could square the circle and trisect any angle.

A fire lighted at night as a signal, or for the use of the watch or guard. ...