The Iron Butt is a large device, used as a replacement of one's butt. It is a large gray and dark blue machine with many wires, gears, pipes, lights, and other things sticking out of it. Concept-wise, it is a machine that doctors use in Bikini Bottom if a patient's butt is severely injured.

The Iron Butt is a parody of a device called the "Iron Lung," which was used for breathing problems because of Polio and Botulism.
One more injury like that and you could wind up like that poor creature there, in the Iron Butt.”

“Oh man, it itches!”
by LawrenceMK2 June 4, 2021
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A nickname for a long-distance motorcyclist. The Iron Butt designation often specifically applies to someone who has motorcycled 1000 miles in a 24-hour period.
"I earned my Iron Butt patch last July when I rode from Poughkeepsie to Jacksonville in last than 24 hours."
by Bill from VA February 13, 2012
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the stinky smell that comes outa a female dogs butthole! its nasty and smells like rustu iron
Peanut has iron butt again!
by trumpetcatz July 31, 2003
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Anything desired so strongly that possessing/achieving THAT SPECIFIC THING becomes an obsession in the mind of the desirer, an obsession that compels them to go to absurd, even destructive, even self-destructive lengths to acquire the thing, sometimes ignoring easier options in the process. The ends do NOT justify the means here, but they "gotta have that butt-iron". Taken from the science video where it is explained how much magnetic force Magneto would have to exert to extract the iron from the guard in X-Men II; long before he could have extracted it, he would have exerted enough magnetic force to escape several times over, but he's "gotta have that butt-iron"
Me: Dude! Why do you need THAT car? We passed three dealerships on the way! I think we ran over a guy back there!
You: I gotta have that butt-iron! I gotta!
by Balloonie-cat1 August 31, 2022
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