Trousers (or pants in Canada, South Africa and the United States, and sometimes called slacks or breeches in more old-fashioned usage) are an item of clothing worn on the lower part of the body, covering both legs separately (rather than with cloth stretching across both as in skirts and dresses). Historically, as for the West, trousers have been 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.
In North America, pants is the general category term, and trousers refers, often more formally, specifically to tailored garments with a waistband and (typically) belt-loops and a fly-front. For instance, informal elastic-waist knitted garments would never be called trousers in the U.S.