crabbed: [13] Because of their tendency to deploy their pincers at the slightest provocation, and also perhaps because of their sidelong method of locomotion, crabs seem always to have had a reputation for being short-tempered and perverse. Hence the creation of the adjective crabbed, which literally means ‘like a crab’. Its meaning has subsequently been influenced by crab the apple, famous for its sourness. (The semantically similar crabby is a 16th-century formation.) [crabbed etymology, crabbed origin, 英语词源]