From Old English 'mearcian,' from PIE *merg- (boundary) — originally tracing territorial boundaries.
To make a visible sign or impression on a surface; to indicate, designate, or pay attention to.
From Old English 'mearcian' (to mark, trace out boundaries, designate, describe), from 'mearc' (boundary, limit, sign, landmark), from Proto-Germanic *markō (boundary, border, sign), from PIE *merǵ- (boundary, border). The original meaning was deeply territorial: to mark was to trace the boundary of a territory, to establish where one domain ends and another begins. The broader sense of making
The word 'margin' comes from the same PIE root *merǵ- as 'mark.' A margin is literally a boundary or border — the edge of a page, the border of acceptability. And a 'marquis' (or 'margrave') was originally a lord of the march, a guardian of the border territory. Marking, margins, and aristocratic titles