Running so hard that you throw up during or immediately after a race. Also can be used to describe the "puke" that is ejected from the person and onto another runner.
He ran so hard during the cross country meet that he was ploofing nearly the whole time.
The act of adding a specific feature onto a theoretically finished contraption or building to stop Grian from tampering with it, which may result in said contraption/building being destroyed in a half a second.
Grian-Proofing may also be used to classify some kind of lock on an object that stops it from being used by normal people that don't have the key.
Guy1: "OK, I think I've finished this massive redstone-only item filter."
Guy2: "Did you Grian-Proof it?"
Guy1: "Oh yeah... Would adding a misc. item bin be sufficient Grian-Proofing?"
Guy2: "Make sure he can't get the items back"
Guy1: >:3