The resulting stench and theoretical stink particulate matter from a fart/flatulent episode. Etymology: slang based on the word "shrapnel", the primary connecting theme being the dangerous particles emitted by the event.
"Dude, you farted right next to me! I know you didn't aim it at me, but the fartnel is gonna be all over me!"
by Halesite May 6, 2010
Get the fartnelmug.