Noun: A piece of private information told in confidence which becomes a weapon when the subject of the information falls from grace in the eyes of the person who holds it. The (mis)use of this information for the purpose of a personal attack is always imminent. Often used as an underhanded form of malicious cockblock.
Verb: The leaking/use of this information.
Mel: My ex-boyfriend Tyler is untrustworthy
Kayla: Do you have any handleshoe?
Mel: He tattooed a life size human eye on the head of his friend's dick
Kayla: That's pretty private. How would you even know that?
Mel: I've got pics.
Kayla: Of his friend's dick? That is some serious handleshoe material. Let me please see this dick pic.
Mel: I fucking hate him. I am going to handleshoe the shit out of him, even if it makes me look equally bad.
Alexa: If you keep handleshoeing people, no one will trust you to tell you anything.
Mel: Then I'll use hearsay and questionable information. I want vengeance, not to contemplate morality.
Alexa: You need a muzzle, woman.
Mel: Then you should try to put one on me, I hear you have a shitload of them.
Alexa: I don't even know what that means!