Speedo

Etymology
From the name of the swimsuit company,, which first designed and manufactured swimwear in Australia that was briefer and sleeker than most other swimwear then available.

Noun

 * 1)  A tight-fitting swimsuit, especially commonly worn by competitive swimmers and divers. Usually implies a brief or bikini style swimsuit.
 * I could tell that she was a serious swimmer, because every time I saw her at the pool she was wearing a Speedo of one design or another.
 * 1)   A male swimsuit, very tight fitting and small, brief-style, and not a thong-type.
 * She called down from upstairs, "He'll be out in a minute: he's just putting his Speedo on."
 * 1)   A male swimsuit, very tight fitting and small, brief-style, and not a thong-type.
 * She called down from upstairs, "He'll be out in a minute: he's just putting his Speedo on."
 * 1)   A male swimsuit, very tight fitting and small, brief-style, and not a thong-type.
 * She called down from upstairs, "He'll be out in a minute: he's just putting his Speedo on."

Usage notes
In US English a Speedo is used for the singular. In Australian English, Speedos is used for both the singular and the plural.

Synonyms

 * See Thesaurus:swim briefs