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The hazy environment created when a room is hotboxed. Although not dangerous to humans, it is known to alter perceptions (since everything apparently becomes much funnier). Either due to recent climate shifts or planetary alignment, Grassmosphere levels increase annually on the 20th of April.
Damn Hippie! I can't breath... or even See!!!
Relax, dude.... just lay back and enjoy the Grassmosphere.
by Dr Hoss April 21, 2011