Speedo

こんな文がありました。
I can't believe you can fit into such a small Speedo.
大文字で始まっているので固有名詞とわかりますが、一応電子辞書を見ました。やはりspeedo = speedometer しか出ておりません。そこでWebで調べると：
Wikipediaに次ぎのような詳しい説明がありました。
A speedo, which takes its name from the swimsuit brand Speedo, may refer to any briefs-style male swimsuit such as those used in competitive swimming, regardless of the actual manufacturer. Such garments are otherwise also referred to as competition briefs, swim briefs, bathers, posing briefs, or racing briefs. The term is most common in Australian English but is also widely used in other English-speaking countries. Speedos were invented by the Australian company, Speedo.

Like the underwear briefs, speedos feature a "V-shape" front and solid back providing form-fitting coverage. They are typically worn below the lower waist. They are secured by a drawstring and thin banding at the upper thighs. Most speedos are made of a nylon and lycra/spandex composite. Suits commonly have an elastic front lining made of similar fabric and are secured around the waist with a cord draw string.
なるほど、水泳選手がこのSpeedoらしき水泳パンツを身に着けているのを見たことがあります。オーストラリア生まれで、小文字で始まるspeedoでも分かるようになっているのですね。