Real Dictionary

wet suit
countable noun: A wet suit is a close-fitting rubber suit which an underwater swimmer wears in order to keep their body warm.

wet suit in American English
a close-fitting rubber garment worn by a skin diver in cold water that allows a thin, insulating layer of water to collect between the diver's skin and the suit in order to retain body heat
a closefitting, usually one-piece suit of rubber, esp. of foam neoprene, worn as by skin divers for warmth

wet suit in British English
noun: a close-fitting rubber suit used by skin divers, yachtsmen, etc, to retain body heat when they are immersed in water or sailing in cold weather