パンツ

ぱんつ
noun
underwear; pants
See also: ズボン (trousers (older term))
1. underwear; underpants
Undergarments worn on the lower body.
パンツ(あら)
I wash my underwear/pants.
I bought new underwear/pants.
These pants are easy to wear.
2. pants; trousers
Outer garments covering the legs.
パンツ(あら)
I wash my underwear/pants.
I bought new underwear/pants.
These pants are easy to wear.

パンツ is a loanword from English 'pants' with two distinct meanings in Japanese.

MEANING 1 - UNDERWEAR:

When used alone, パンツ most commonly means underpants/underwear in everyday speech.

MEANING 2 - TROUSERS/PANTS:

In fashion contexts, パンツ refers to outer garments (trousers).

DISTINGUISHING TERMS:

USAGE NOTE:
Context usually makes the meaning clear. Fashion magazines and stores use パンツ for trousers, while in daily conversation it typically means underwear.