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delineation; demarcation
drawing a line (e.g. between what's acceptable and unacceptable)
(measuring) ruler
プライバシーの線引きは難しい。
Demarcating privacy is difficult.
どこで線引きするか議論された。
It was debated where to draw the line.
委員会は許可用途と禁止用途の線引きを明確にした。
The committee clearly demarcated permitted and prohibited uses.