Dram (volume) - Definition and Overview

The dram (American spelling) or drachm (British spelling) is a small imperial unit of volume; it is also called the fluidram (contraction of fluid dram). It is defined as 1/8 of a fluid ounce, which means it is exactly equal to 3.696 691 195 312 5 mL in the U.S. and 3.551 632 812 5 mL nearly everywhere else.

Dram is also used informally to mean a small amount of liquid, especially Scotch whisky.