crab /kræb/ BrE AmE noun
[ Sense 1-3: Language: Old English ; Origin: crabba ]
[ Sense 4: Date: 1800-1900 ; Origin: crabbed ]
1 . [countable] a sea animal with a hard shell, five legs on each side, and two large ↑ claw s ⇨ crustacean
2 . [uncountable] the flesh of this animal that you can cook and eat:
crab meat
dressed crab (=prepared for eating)
3 . crabs [plural] informal a medical condition in which a type of ↑ louse (=insect) is in the hair around sexual organs
4 . [singular] American English informal someone who becomes annoyed easily about unimportant things