A meeting that takes place between co workers in order to fuck over another co worker. Can also be a meeting between so called friends in order to fuck over one of their buddies.
Hey man we need to see you tonight after work. We are having a knife in the middle of the back meeting. Yeah I know we have to hang Tom out to dry for that bullshit he pulled last week. He thinks he fucked us over but we are going to get him in the end.