Definition of lockdown
1 : the confinement of prisoners to their cells for all or most of the day as a temporary security measure
2 : an emergency measure or condition in which people are temporarily prevented from entering or leaving a restricted area or building (such as a school) during a threat of danger < … the school went on lockdown when a student brought a pellet gun to campus. — Ian Gordon>
First Known Use of lockdown
Legal Definition of lockdown
: the confinement of prisoners to their cells for a temporary period as a security measure
Seen and Heard
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