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active shooter

American  
[ak-tiv shoo-ter] / ˈæk tɪv ˈʃu tər /

noun

  1. a person who is presently using a gun to shoot people in a confined and populated area.


Etymology

Origin of active shooter

First recorded in 1965–70

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

We equip them with protective gear to respond to a chemical attack; we train them in heavy weapons to respond to an “active shooter” or terrorist event.

From The Wall Street Journal

The Department of Homeland Security said the off-duty ICE agent was responding to an “active shooter.”

From Los Angeles Times

The police responded by deploying officers to the scene, and issuing an active shooter alert for the rural community and a surrounding area.

From BBC

A spokesperson for the Department of Homeland Security initially said an off-duty Immigration and Customs Enforcement agent who lived at the same apartment complex was responding to a suspected “active shooter” when he opened fire.

From Los Angeles Times

Local police have refrained from using the Department of Homeland Security’s characterization of Porter as an “active shooter.”

From Los Angeles Times