|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
A grain is a unit of measurement of mass, and, for the troy grain, equal to exactly 64.79891 milligrams. It is nominally based upon the mass of a single seed of a cereal.
The short ton is a unit of weight equal to 2,000 pounds (907.18474 kg), that is most commonly used in the United States where it is known simply as the ton.