(usually in the plural) a garment extending from the waist to the knee or ankle, covering each leg separately
"he had a sharp crease in his trousers"
An article of clothing that covers the part of the body between the waist and the ankles or knees, and is divided into a separate part for each leg.
"He pulled up his trousers to make sure they were properly tucked into his boots before starting work."
In plain English: Trousers are pants that cover both of your legs from your waist down to your ankles.
"He put on his trousers before stepping outside to meet his friends for lunch."
Usage: Trousers are typically worn as an outer garment rather than underwear, distinguishing them from leggings which fit tightly against the skin. While often used interchangeably with pants in casual speech, trousers usually implies a more formal style or specific cut like dress slacks.
The word trousers comes from Middle Irish triubus, meaning "close-fitting shorts." It entered English in the late 16th century and was later adapted with an extra 'r' to match similar words like drawers.