A unit of volume, used in various ways but most commonly equal to 40 cubic feet (1.13267 cubic meters). This makes it the same as the freight ton (See: Ton [5])
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}