also: すえっとぱんつ
noun
sweatpants; tracksuit bottoms; joggers
Casual, soft trousers often worn for lounging or light exercise. In Japanese, typically refers to the same garment as in English.
今日は一日中スウェットパンツで過ごした。
I spent the whole day in sweatpants today.
ジムに行くときはスウェットパンツが楽だ。
Sweatpants are comfortable when going to the gym.
Borrowed from English 'sweatpants', with the typical katakana adaptation.