1 definition by Rukusan

A unique kind of orgasm only available to LSD users and Lord of the Rings fans.

When you ejaculate, the semen morphs into a small wizard statuette, then starts glowing, and a voice is heared yelling the words: "YOU SHALL NOT PASS".

A female version of this has not yet been discovered.
"OMG! I just had a Gandalfgasm!"
by Rukusan August 6, 2005
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