short ton

The short ton (S/T) is a unit of mass equal to 2,000 lb (exactly 907.18474 kg). In the United States it is often called simply ton without distinguishing it from the metric ton (or tonne, 1,000 kilograms) or the long ton (2,240 pounds)—rather, the other two are specifically noted. There are, however, some U.S. applications for which unspecified tons normally means long tons (for example, Navy ships) or metric tons (world grain production figures).
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Noun
1. a United States unit of weight equivalent to 2000 pounds
(synonym) ton, net ton
(hypernym) avoirdupois unit
(part-holonym) kiloton
(part-meronym) hundredweight, cwt, short hundredweight, centner, cental, quintal

A unit of weight equal to 2,000 pounds. (DOE3) (DOE5)

Common measurement for a ton in the United States. A short ton is equal to 2,000 lbs or 0.907 metric tons. See metric ton.

Two thousand pounds. By contrast, a long ton equals 2,240 pounds. A metric ton equals 2,204.62 pounds.