A hospital scenario where a massive amount of patients come in all at once--possibly more than can be handled.

This then leads to a triage that needs to be done where the doctors put patients into categories, who needs surgery immediately, who can wait, and who's most likely to die.
There was a bad accident today and the hospital got hit with mass casualties.
by OwenJoker February 02, 2010
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Any weapon that is designed to kill large numbers of people, without necessarily destroying property. However, they may also cause enormous damage as well.
Anthrax, sarin nerve gas, and nuclear weapons all fall under this category.
by Pinto July 31, 2003
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