catgut

/ˈkætˌɡʌt/noun
High School
1

A cord of great toughness made from the intestines of animals, especially of sheep, used for strings of musical instruments, racquets, sutures etc.

2

The material from which such cords are made.

3

A sort of linen or canvas, with wide interstices.

4

Tephrosia virginiana (goat's rue, devil's shoestring).