Sĭs'trum, n.

noun

n. [Lat., Gr. σεῖστρον, from σείειν, to shake.] A kind of timbrel consisting of a thin oval metal frame, through which passed a number of metal rods, and furnished with a handle by which it was shaken. It was peculiarly Egyptian, and used especially in the worship of Isis. Fairholt.

An ancient sistrum, a handheld musical instrument with a loop-shaped frame and crossbars.
Sistrum.