Emily Dickinson Lexicon

RUL-ER, n.

1. One that governs, whether emperor, king, pope or governor; any one that exercises supreme power over others.
2. One that make or executes laws in a limited or free government. Thus legislators and magistrates are called rules.
3. A rule; an instrument of wood or metal with straight edges or sides, by which lines are drawn on paper, parchment or other substance. When a ruler has the lines of chords, tangents, sines, &c. it is called a plane scale. Encyc.