Crabs and their close relatives have 10 legs, arranged in five pairs. Some of their legs are used for walking, while others are used for swimming or defense.
Definition of plunge for English Language Learners. : 1  a sudden fall or jump usually from a high place. : 2  a sudden quick fall in amount, value, etc. : 3  the act of suddenly beginning to be in a particular condition or situation.
take the plunge commit yourself, go for it, go all out, throw caution to the wind, jump in at the deep end (informal), give it your all She decided to take the plunge and expand her business. plunge verb