A claw was a type of manipulatory appendage, found at the end of fingers.
The sapient species of Macra were larger than humans, able to hold a human in one claw. (TV: The Macra Terror) After devolving in the far future, the Macra grew much bigger, and were large enough to easily hold an entire New Earth car in their claws. (TV: Gridlock)
The Abzorbaloff had hands with three clawed fingers, which exposed him as alien to Ursula Blake and Elton Pope when he attempted to hide behind a copy of The Daily Telegraph newspaper. Ursula was absorbed into the Abzorbaloff's body when his hand grabbed her arm. (TV: Love & Monsters)