What is Gewehr?
1.
german or many other eastern european languages for rifle
FG-42 = Fallshimjager Gewehr 1942
See
2.
Verb
Popularized by Call of Duty: World at War online play.
To gewehr is to be unexpectedly presented with an enemy soldier/player, and instinctively pull the trigger, resulting in the enemy/player's death.
"Oh fuck dude, I was just running around and buddy fucken popped outta the door way and I gewehr'd him in the fucken face!"
See