Speedos

Etymology 1
From the name of the swimwear company, Speedo.

Noun

 * 1)  A tight-fitting brief or bikini style swimsuit.
 * She called down from upstairs, "He'll be out in a minute: he's just putting his Speedos 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.

Noun

 * She always had two spare Speedos for her swimming competitions away from home.
 * She always had two spare Speedos for her swimming competitions away from home.