Claw
A claw is a curved, pointed keratin structure extending from the end of a digit. It can grip, tear, dig, climb, or defend, depending on the animal.
Digit: A finger or toe, including the terminal bones and soft tissues of a limb. A claw grows from the end of a digit and is anchored to its tissues.
Retractable claws: Claws that can be withdrawn toward the digit and extended when needed. Cats keep these claws protected and sharp between uses.
Claw growth: The production of new keratin that lengthens a claw from its growing base. Continuous growth replaces material lost through wear.
Cat claw: A sharply curved, retractile claw at the end of a cat’s digit. Its retractile design preserves sharpness for climbing, hunting, and defense.
Keratin: A family of fibrous structural proteins found in skin, hair, nails, feathers, and other tissues. Keratin forms the hard material of claws.
Talon: A large, strongly curved claw on the foot of a bird of prey. Raptors use talons to seize and kill prey.
Claw retraction: The movement that withdraws a claw toward the digit without retracting its keratin sheath. Tendons and joints let cats extend or protect their claws.
Armadillo claw: A large, strong claw on an armadillo’s forefoot, adapted for digging. Armadillos use prominent foreclaws to excavate burrows and uncover food.
Unguis: The hard, horny outer part of a claw or nail. This anatomical term names the keratinized sheath that makes up the claw.
Ossicone: A permanent, skin-covered bony projection on the head of giraffes and okapis. Ossicones can look claw-like in form but are not keratin structures on digits.