Definition of "undersuit" [un•der•suit]

• A soft undergarment worn by divers and astronauts (noun)
• Any suit worn under another suit; a suit of underclothes. (noun)

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• "He was, however, in much discomfort, as the armor and the scale metal undersuit weighed so much that the carpenters had to make him a special leaning board and chair to take some of the weight."
• "Amongst the beautiful stuff Saxon went over, she found a nightgown and a combination undersuit of her own manufacture."
• "Crew wear a thermal undersuit underneath an all-in-one dry suit, complete with steel-plated wellies and inflatable knee pads, as well as a life jacket which can support up to four people in the water."