What is the difference between sinew and tendon?

Question

I wonder what the difference between sinew and tendon is. I searched for it but didn't get any clear answer:

https://www.quora.com/Whats-the-difference-between-sinew-and-tendon:

They are often used interchangably but to be technical, a tendon connects a muscle to a bone. The term sinew also seems to include ligaments which connect bones to bones. It is however, not a medical term.

https://answers.yahoo.com/question/index?qid=20070410182936AA2Kcnk

Sinew is another word for muscle which is the functional unit of movement.

Tendons connect bone to muscle to make movement possible: The muscle contracts and pulls the bone that it's connected to Source(s)

http://the-difference-between.com/tendon/sinew :

Sinew is a synonym of tendon. As nouns the difference between sinew and tendon is that sinew is (anatomy) a cord or tendon of the body while tendon is (anatomy) a tough band of inelastic fibrous tissue that connects a muscle with its bony attachment.

http://www.thefreedictionary.com/sinew

sinew = tendon

https://en.wikipedia.org/wiki/Tendon

A tendon (or sinew) is a [...]

Is sinew a synonym for tendon, and if not what is the difference?

Answer 1

They get used somewhat interchangeably, which blurs the lines on the definitions.

When I had my anatomy classes, sinews were regarded as an inclusive class, which included both ligaments and tendons.

For the breakdown:

• Tendon: Fibrous tissue that connects muscle to bone.
• Ligament: Fibrous tissue that connects bone to bone.
• Sinew: Includes both of the above.

Answer 2

A tendon is a fibrous connective tissue which attaches muscle to bone. Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure. A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable. So sinew = tendon. Sinew is a bit more general and somewhat ambiguous. It is mostly used today synonymously with tendon, but historically it has been used to mean either tendons or ligaments, or even to mean muscle.