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underpants; pants; briefs; panties; shorts; knickers
trousers (esp. women's); jodhpurs; breeches; pants; trunks (e.g. swimming)
新しいパンツを三枚買った。
I bought three new pairs of underwear.
子どもがパンツを裏返しに履いていた。
The child was wearing their underwear inside out.
洗濯したパンツを引き出しにしまった。
I put the washed underwear away in the drawer.