de ‧ mar ‧ ca ‧ tion /ˌdiːmɑːˈkeɪʃ ə n $ -ɑːr-/ BrE AmE noun [uncountable] formal
[ Date: 1700-1800 ; Language: Spanish ; Origin: demarcación , from marcar 'to mark' ]
1 . the point at which one area of work, responsibility etc ends and another begins
demarcation between
traditional lines of demarcation between medicine and surgery
2 . the process of deciding on or marking the border between two areas of land
demarcation of
the exact demarcation of the north-south boundary