What is the meaning of Catgut?

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

The material from which such cords are made.

A sort of linen or canvas, with wide interstices.

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

catgut

Source: wiktionary.org