# Definition:Avoirdupois/Ounce

## Definition

The ounce is an avoirdupois unit of mass.

 $\ds$  $\ds 1$ ounce avoirdupois $\ds$ $=$ $\ds 16$ drams $\ds$ $=$ $\ds 437 \cdotp 5$ grains $\ds$ $=$ $\ds 28 \cdotp 34952 \, 3125$ grams $\ds$ $=$ $\ds 0 \cdotp 02834 \, 95231 \, 25$ kilograms

The gram / kilogram equivalent is defined to be exact.

### Symbol

$\mathrm {oz.}$

The symbol for the ounce is $\mathrm {oz.}$

The $\LaTeX$ code for $\mathrm {oz.}$ is \mathrm {oz.} .

## Linguistic Note on Avoirdupois

The word avoirdupois derives from the Norman French word whose literal translation is goods (that is property, or things owned) of weight.

The avoir part also means to have in modern French, and derives from the Latin habere.

It is pronounced something like av-wah-doo-pwah, although Francophones will be aware that there are further subtleties to this.

## Linguistic Note on Ounce

The word ounce derives from the Latin uncia, meaning $\dfrac 1 {12}$ part (of an as).

Despite the gradual migration to the metric system, the word ounce still lives on as a rhetorical flourish for something small, for example:

If you only had an ounce of sense you would understand that ...