demarcation point

基本解释

The incident is the latest in a line of military encounters at the Northern Limit Line (NLL), the de facto demarcation point at which North and South Korean waters meet.
该事件是北方分界线上一连串军事冲突的最新一起，而实际的分界点是在朝鲜和韩国相接的水域。
Industrial Revolution was the demarcation point of human history, and the policy of private forests subsidies were also brought forward and applied in such special period.
工业革命是人类历史的分界点，而有关私有林的补贴政策也在这样特殊时期提出、应用。
After the functional relation between designed flow rate and water demand unit is analyzed, the concept of demarcation point of water supply is put forward, which is convenient for actual .
文章通过实例，详细讨论了三种计算方法的合理性，通过讨论设计流量与用水单位数之间的函数关系，最后提出给水分界点的观念，便于工程实际应用。

But I would say in 2005 is really the demarcation point.
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The actual demarcation point will come when vendors receive firm orders for volume production which normally occur 12-16 weeks before a phone appears on the shelf.
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