This term mainly relates to online games in which a single player kills off all of the remaining enemies or wipes out the entire opposing team by itself. More simply put as, one person defeated everyone else.

This term may also work in real life situations such as paintball, air soft, some sports and even in war/combat zones.
Red Team Player #1: "WOW our whole entire team has been killed off accept for one guy, and there is four more left on the blue team"

Red Team Player #2: "Yeah, we got no chance here"

(Red Team Player #3 kills everyone on the blue team and wins the match for the red team)

Red Team Player #4: "Holy Crap he killed them all just by himself!"

Red Team Player #3: "Yeah dude they just got Mono Fucked"
by Fireblac February 23, 2010
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