Fartnoid Share definition Flag Paranoid of smelling a fart or someone who always smells phantom farts. McGee: Did you fart? I smell a fart. (when actually no one farted). McGee, you are a Fartnoid, you are so paranoid of farts that you think you smell farts even when no one has farted! Fartnoid by watunoabootdat December 20, 2010 Get the Fartnoid mug.