\begin{definition}[Definition:Apothecaries' Weights and Measures]
The '''apothecaries' (system of) weights and measures''' is a system of mass and volume units, derived from the Roman system.
They were used by physicians and apothecaries for medical recipes, and also sometimes by scientists.
Although in some cases bearing the same names as their imperial counterparts, the actual units themselves were subtly different in size.
\end{definition}