A crustacean with a broad carapace, stalked eyes, and five pairs of legs, the first pair of which are modified as pincers. Crabs are abundant on many shores, especially in the tropics, where some have become adapted to life on land. A louse that infests human body hair, especially in the genital region, causing extreme irritation. A machine for picking up and lifting heavy weights. An irritable person. Move sideways or obliquely. Fish for crabs. Grumble, typically about something petty. Act so as to spoil.