To rip a fat one is to rip a massive fart that could potentially cause an earthquake or rip a large hole in the pants.
This fart is usually extremely stinky, pretty much equivalent to the same gas used in world war 2 by the nazi executioners.
Jared - "Oi Atef! Rip a fat one!"
Atef - "*Rips a fat one*
by Atef Lord February 08, 2021
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