demarcation
n. C / Un. a clear line or mark that shows where one area, object, or group ends and another begins. It helps people know exactly where they are allowed to be or what they are responsible for.
n. a line or mark that indicates a boundary or limit. Often refers to the specific limits of a territory, a role, or a set of responsibilities.
The white line on the road is a clear demarcation of the lane.
The new fence served as a physical demarcation between the two neighboring properties, ending years of boundary disputes.
The treaty established a strict demarcation of the border, ensuring that both nations could exercise sovereignty over their respective territories without further conflict.
First recorded c.1752, from Spanish línea de demarcación and/or Portuguese linha de demarcação, the demarcation line laid down by the Pope on May 4, 1493, dividing the New World between Spain and Portugal on a line 100 leagues west of the Cape Verde Islands. Both derive from demarcar, from de- + marcar (“to mark”), from Italian marcare, from the same Germanic root as march.