Sinew (noun)

A cord or band of tough, fibrous tissue that connects a muscle to a bone.

Origin:

Middle english sene, from old english sēne; akin to old high german sīna sinew and perhaps to latin sēnus aged.

Examples:

1. He strained a sinew in his leg while running.
2. The sinews of the arm are responsible for movement.
3. The sinews of the back are important for support.
4. The sinew was stretched to the limit.
5. The sinew is an important part of the musculoskeletal system.