Trousers can be defined as an outer garment for covering the body from the waist to the ankles, divided into sections to fit each leg separately. Historically, as for the West, trousers were the standard lower-body clothing item for males since the 16th century; by the late 20th century they had become extremely prevalent for females as well. Trousers are worn at the hips or waist, and may be held up by their own fastenings, a belt, or suspenders (braces).

Leggings are form-fitting trousers of a clingy material, often knitted cotton and lycra. Trousers can cover the body from the waist all the way down to the top of the foot, or stop almost anywhere from the upper thigh to the ankle. Short trousers, or just shorts, stop anywhere from the upper thigh to the knee.

Trousers also trace their ancestry to the individual hose worn by men in the 15th century. Trousers were introduced into Western European culture at several points in history, but gained their current predominance only in the 16th century. It is customary in the Western world for men to wear trousers and not skirts or dresses.