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1.
When one has smoked marijuana/gotten high then proceeds to say or do something incredibly stupid, so stupid that an observer who sees/hears this event feels the urge to call out this stupidity with a "Stoner Foul", which 1) forces the individual to stand up or sit down (the opposite of which one they are doing at the time of the stoner foul) and 2) succinctly points out the flaw/terrible idea/fuck up for everyone to hear.
Travis: "Man, instead of making expensive bombs and wasting money, the government should just make a bomb full of pennies cause if you drop those from like something high, it would kill someone, so a penny bomb would be awesome"

Josh: "Stoner Foul"
by JR2112 July 19, 2010