Like spooning, butter knifing is laying together with one or more people. Unlike spooning, you lie completely straight like a butter knife and you don't even have to touch the other person. Looks a lot like planking face up or a corpse in a coffin.
Player 1: She won't get out of my bed.
Player 2: Spoon her.
Player 1: No. Spooning is gross. I'm gonna lay next to her like I'm dead. Look we're "butter knifing".
Player 2: You should put that onUrban Dictionary before someone else does. What would forking be?
Player 1: We all know what "forking" is.
Player 2: Painting your toenails is hard.
Player 3: Wait. Look. Do I look dead yet?
An action performed in Modern Warfare 2; used when talking about somebody who repeatedly uses the tactical knife attachment to perform kills. It's frequently paired with the perk Commando. This is a tactic commonly used by players deemed as a hiker.
Guy 1: Tac knifing is for n00bs!
Guy 2: What are you talking about? You were tac knifing yesterday when you called in that nuke at Sub Base!
Guy 1: I was tac knifing your mom last night.
Guy 2: ...