ONE PIECE BIKINI (SWIMSUIT)
A swimsuit, bathing suit, or swimming costume is an item of clothing designed to be worn by men, women and children while they are engaging in a water-based activity or water sports, such as swimming, water polo, diving, surfing, water skiing, or during activities in the sun, such as sun bathing.
A swimsuit can be worn as an undergarment in sports that require a wetsuit such as water skiing, scuba diving, surfing, and wakeboarding.
Swimsuits are known under a variety of terms.
For example, in New Zealand, swimsuits are almost always called togs or, occasionally, bathers.
They are less commonly called "cossies" (short for "costume"), which along with "bathers" is the Australian term.