| Noun | 1. | system of weights - a system of units used to express the weight of something system of measurement, metric - a system of related measures that facilitates the quantification of some particular characteristic avoirdupois, avoirdupois weight - a system of weights based on the 16-ounce pound (or 7,000 grains) troy, troy weight - a system of weights used for precious metals and gemstones; based on a 12-ounce pound and an ounce of 480 grains |