lockdown
noun /ˈlɒkdaʊn/
/ˈlɑːkdaʊn/
[countable, uncountable] (especially North American English)- an official order to control the movement of people or vehicles because of a dangerous situation
（对人或交通工具的）活动限制，行动限制 - a three-day lockdown of American airspace
美国为期三天的领空关闭 - Prisoners have been placed on lockdown to prevent further violence at the jail.
已对囚犯实行活动限制，以免狱中再出现暴力行为。 - The prison governor ordered an instant lockdown (= prisoners were locked in their cells).
监狱长下令立即封锁。 - The city schools were in lockdown.
城市学校被封锁了。
- a three-day lockdown of American airspace