A crab is a stubby sea creature with a flat body, eight legs, and claws. You can sometimes find tiny crabs in the sand on the beach.
Crabs have a thick, shell-like covering called an "exoskeleton," and you can find them in both fresh and saltwater. Some types of crab are considered a delicacy, with sweet, delicate flesh often called "crab meat." There are many shelled sea creatures with crab in their names, like horseshoe crabs and hermit crabs, that aren't true crabs. The word crab comes from a Germanic root related to the Low German krabben, "to claw."