a dose of gunpowder and colourant mixture which is placed on top of the butthole and combusts with a rapid expulsion of methane from sed butthole (otherwise known as a 'fart' or 'guff') to produce a pyrotechnical display, similar to the firework displays introduced to the world by the chinese.
dave's left and right buttcheeks were severely disfugured after a pyro flatuence show that went horrendously wrong, now u can see the face of har mar super star between the crack.
by Anonymous September 30, 2003
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