Crab can refer to one of several things:

• Crab, the animal
• The crabb is a creature that represents Cancer (constellation) in astronomy and Western Astrology June 22-July 23.
• Crab apple: a kind of tree, in the genus Malus.
• Crab, any of various machines used to hoist heavy objects.
• A crab landing is a method of landing a fixed-wing aircraft in a crosswind, so named because crabs often walk sideways.
• A crab is a type of misapplied stroke in Watercraft rowing when the oar is pulled round past the oarsman.
• A crab is a type of scratching turntablists use, involving flickering the crossfader between your thumb and your fingers, starting with the pinky and ending with the index.
• Crabs is also the common slang term for pubic lice.
• LMS Hughes Crab, a type of steam locomotive;
• Crab is an instruction given by a film director or television director to a camera operator requiring a sideways movement of the camera.
• Crab is maritime slang for a carabiner.
• Crab is a disrespectful term to Crips gang members.
• Crab, an athletic move akin to the float in breakdancing.