Bow-compass

Bow´-com`pass


n.1.An arcograph.
2.A small pair of compasses, one leg of which carries a pencil, or a pen, for drawing circles. Its legs are often connected by a bow-shaped spring, instead of by a joint.
3.A pair of compasses, with a bow or arched plate riveted to one of the legs, and passing through the other.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.