An alias for double underscore, "__". Specially useful in the Python computer language, in which names like "__init__" are common. Coined as a speech shorthand.
Eric: So the problem is initdata? (the method initdata() )
John: Nope, dunder init dunder is where things start to go wrong... (__init__)
"make sure to wash your dunders" "Dunderwear, clothes for the working man" "Dunderwear soft enoughf for a mans buttox, toughf enough to handle the swamp ass of a working man"