extended claw
A cat uses its claws only when necessary, mainly for climbing or killing its prey.
plantar pad 
Thick cutaneous bulge, elastic and resistant to wear, supporting the metacarpus; the cat uses it to move about and it absorbs shocks.
digital pad 
Thick cutaneous bulge, elastic and resistant to wear upon which the toe rests; it contributes to locomotion and absorbs shocks.
elastic ligament 
Strong and elastic fibrous tissue located on the back of the distal and median phalanges allowing the claw to retract into the sheath.
tendon 
Fibrous tissue connecting the muscle to the bone; the tendon’s traction causes the claws to extend.