from the GNU version of the Collaborative International Dictionary of English
- n. a weight of 29,1662/3 grams.
- A weight of 29.166 + grams used in assaying, for convenience. Since it bears the same relation to the milligram that a ton of 2000 avoirdupois pounds does to the troy ounce, the weight in milligrams of precious metal obtained from an assay ton of ore gives directly the number of ounces to the ton.
Sorry, no etymologies found.