A booger (dried nasal mucus) that gets hard and sharp enough to stab or cut the inside of your nostril. It can result in pain and sometimes a nosebleed.
"Dude your nose is bleeding, what's wrong with you?"
"The low humidity today gave me a really bad knife booger and it cut me when I was trying to pick it out."
To hijack someones belongings without the owner knowledge. In most cases the owner was not present during said hijack.
"Logan, did you boogerjack my pencil?" "No I think Steven was using it." "Steven did you boogerjack my mechanical pencil?" "The red one, yea I used it and stuck it in my bag when you werent here."
"I want my Donkey Kong Country cartridge back that you boogerjacked from my house while I was taking a dump."