As far as I see they mean exact same thing and some people do not realize it. Also, superfluous when “swimsuit, !one-piece swimsuit” accomplishes same results, plus-minus all untagged one-pieces.
Also add a description to “bikini” to the following point:
“Swimwear consisting of a separate chest-covering and crotch-covering apparel. For non-separate, see one-piece swimsuit
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