Showing up unannounced or uninvited to someone's place of residence, work site, or hangout. (Pronounced "Doh Pop")

Intelligence agency term for "psychological operation". A government or corporate-sponsored operation, usually taking the form of a "terrorist attack" or "crazed gunman on a spree", with the intent of panicking the public into demanding more police and laws inhibiting freedom. Psyops are usually carried out by drugging a civilian or group of civilians with aggression-promoting drugs, psyching them up, arming them, and sending them out to commit mayhem. Government-sponsored terrorism. See also blackshirts, conspiracy

The old South Side of Chicago social custom of shooting
through the door at unwanted visitors.