ounce

Roots traceable to the Roman Empire period

Symbol: oz / Base data: mass. Imperial units.
1 oz = 1/16 lb = 28.349527 g *The definition of an avoirdupois ounce is shown on the left

The current weight was settled in the period of Queen Elizabeth I

The word derives from Latin uncia, which meant one-twelfth (1⁄12) in the Roman period. It is set at one-twelfth of the Roman pound (libra), which is six silver denarii coins (27 g). This unit spread to the UK, and the avoirdupois ounce was settled at about 28 g during the period of Queen Elizabeth I. One pound was set at 16 ounces.