When someone offers you their handkerchief to wipe your face, butt instead you wipe your ass with it.
Ah damnit Duncan, you made it a stankerchief!
A non reusable cloth that guys use to blow their nose, wipe off sweat, palm, blow their nose again, then finally put it in their pocket.
Me: hey Jim, why did you grab an extra paper towel from the bathroom?
Jim: I’m using it as my stankerchief, because I have a really bad runny nose today.