look up any word, like ratchet:
 
1.
A bowel movement characterized primarily by substantial heat in and around the anal sphincter, often accompanied by severe gut rot. This condition is caused by the consumption of spicy food, like jalapeno peppers or buffalo wings. Firedump will often cause extended visits to the washroom and can drastically inhibit one's productivity for the rest of the day.
The morning after eating a dozen hot buffalo wings and nachos with jalapenos, Patrick sat on the toilet for over an hour as his firedump burned his asshole.
by danpatcon December 01, 2010
 
2.
When you light your shit on fire in the toilet
I just let out a huge shit and lit it on fire, resulting in a fire dump!
by GhastMarine February 29, 2012