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1.
An insult in which the mushroom-fetius-E has a baby mushroom in their brain from either too much shrooms or being a hater on via: facebook; twitter; myspace; etc. Against family or friends.
Example: john was telling sally about his trip to his families house and how stupid he thought his cousin was being. And in reply sally said, "your being a total Mushroom-fetius"

john:" i was like all 'dude you don't have to shove all that in your face. Gosh he is so stupid..."
sally: " john, everybody is dumb in a way, but your being a total mushroom-fetius."
by yamazaimoku sisters July 02, 2011