According to a Ouija board ghost, it is a slang word for having fun in the afterlife. It is unknown how to play the game "gurmf" or what it is, but it is known that having fun is invovled and doing drugs is not invovled in doing Gurmf.

This was said to us on Saturday, October 28th, 2006, by a 14 year old spirit named Beth. She was from France and died at a young age due to an overdose on an unknown drug at a party with her twin brother John.
Man, I had tons of GURMF at that party last night, didn't you Casper?
by Emmy & Lauren October 29, 2006
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