Meaning

noun the boundary of a specific area

noun a conceptual separation or distinction

originFirst 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.

Etymology from Wiktionary, CC BY-SA 3.0