1. Video games. The achievement proclaimed by the announcer, in League of Legends, when a player kills five enemy players in quick succession.
EX. You know what's cooler than watching a .gif of an old man performing a pentakill? Watching someone with no fore-arms or hands get a pentakill by playing with his elbows and foot. To put things in perspective, the odds of getting a pentakill, according to the game maker's statistics, is 1 in 1,500 games.