A bathing costume
One who bathes (cleans oneself with water, for example in a bathtub).
One who immerses oneself in water for pleasure or refreshment: one who swims (for example at a lake or beach).
A sunbather
One who gives a bath to another.
A one-piece swimsuit, which may cover both the chest and the crotch (as contrasted with a bikini, which consists of two pieces).
The lower part of a bikini without the upper part (i.e., topless).