Sweatpants (noun)

A type of casual pants made from a soft, absorbent fabric, typically worn for exercising or lounging.

Origin:

Sweat + pants. likely coined in the 20th century.

Examples:

1. He was wearing a t-shirt and sweatpants.
2. She put on a pair of sweatpants after her workout.
3. I always wear sweatpants when I'm working from home.
4. The store was selling different styles of sweatpants.
5. He was lounging on the couch in his sweatpants.