One or more subjects who participate in a shooting spree, demonstrating their intent to continuously harm others.  Their overriding objective appears to be mass murder, rather than other criminal conduct, such as robbery, hostage taking, etc.  
The first officers on scene engaged the ACTIVE SHOOTER in the main hallway of the school.
by Shane E Smith April 26, 2007
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An active shooter is someone who gets a lot of consecutive hoops in basketball.
“Tyler is an active shooter today”
“I got sent to the principal’s office because I yelled “ACTIVE SHOOTER IN THE BUILDING!!”
by Sigma Male Overachiever August 12, 2023
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A shooter who is not passive by nature.
The active shooter was always active in the community, always motivated, always doing fun things like skydiving or rock climbing. Perhaps the active shooter just got bored due to lack of activity. The active shooter was never passive or hesitant at any time.
by The Original Agahnim January 18, 2022
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