Claw

Curved, pointed appendage at the end of a digit of a mammal, bird, or reptile

A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles, spiders, and velvet worms have somewhat similar fine, hooked structures at the end of the leg or tarsus for gripping a surface as they walk. The pincers of crabs, lobsters, crayfish, shrimps, prawns and scorpions, more formally known as their chelae, are sometimes called claws.

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