I think down under we call it a body suit???
not the same
A rash guard is a thin shirt typically and can be made even of spandex that is worn to prevent rash or sunburn. It is typically worn to surf, sail, kayak, or dive.
A wetsuit, on the other hand, is a garment typically made of neoprene that is typically worn by surfers, divers, body surfers, windsurfers, or others who are actively involved in the water. A rash guard typically covers just the shoulders, arms, torso, and upper chest while a wetsuit typically covers the body from the shoulders to the feet.