crab /kræb/ I. n.［c］螃蟹：All the shops on the seafront had crab for sale.海滨地区的全部商店都出售蟹。‖II. vt. & vi.捕蟹；如螃蟹横行：He began crabbing sideways across the roof.他开始斜行，横着走过屋顶。