Headglitching
A common multiplayer glitch in the Call of Duty series: it involves crouching/standing behind an object that appears to your opponents to cover you all the way up to the eyes or even completely even though from your POV you are visible from the waist up. It will appear to other players that bullets are coming out of your scalp while your gun is buried in a wall.
Headglitching is super annoying on every Black Ops 2 map.
Headglitch
Stuff that pussies do in FPS games to gain an advantage against a player.
Me: *dies* WOOOOW THAT LITTLE EGG IS HEADGLITCHING ON STAIRS.