trouser (Noun) — (usually in the plural) a garment extending from the waist to the knee or ankle, covering each leg separately. ex. "he had a sharp crease in his trousers"
trouser (Noun) — A garment (or part of a garment) designed for or relating to trousers. ex. "in his trouser's pocket" ex. "he ripped his left trouser on the fence"