Originated from a game of Scarbles (fake Scrabbles).

An adjective, it means to be nasty and have an attitude. Usually meant to describe someone who is being short, rude and sarcastic.
Unicorn Master: "Hey, what the hell is up with your boyfriend?! I asked him to hang out and he snapped at me."

Asian Panda: "Forget him. He's just grintzy because I didn't give him any last night."
by Unicorn Master March 5, 2009
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