A crab is any of various crustaceans with four pairs of legs, a pair of pincers, a flattish shell, and a short, broad abdomen folded under its thorax.
- Purse crab
- Fiddler crab
- Mole crab
- Horshoe crab
- Lady crab
- Oyster crab
- Spider crab
- Stone crab
- Ghost crab
- Hermit crab
- Blue crab
"Crabs" is a slang term for pubic lice.
A crab is any of various machines used to hoist heavy objects.