The avoirdupois (IPA: [ˌævərdəˈpɔɪz]; French:[avwar'dypwa]) system is a system of weights (or, properly, mass) based on a pound of sixteen ounces. It is the everyday system of weight used in the United States. It is still widely used by many people in Canada and the United Kingdom despite the official adoption of the metric system, including the compulsory introduction of metric units in shops. It is considered[citation needed] more modern than the alternative troy or apothecary or the medieval English mercantile and Tower systems.
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