A slang noun describing an accidental act of greatness, achieved usually through an act of great stupidity.

Context: "I have pulled a Homer."

The term derives from The Simpsons, in which the character Homer Simpson must avert a nuclear disaster. Being completely incompetent as a safety technician at the nuclear power plant in which he works, he simply presses a few buttons at random via the time-honored method of "eenie meenie miney moe". He averts the disaster, and is hailed a national hero. When it is made known that his actions were guesses, he is shamed, and the term is coined across the nation (both fictionally and in reality, as The Simpsons is no doubt one of the most quoted television shows of all time). At the end of the episode, a basketball player accidentally misses a shot by a wide margin, but through some series of remarkable bounces it makes it into the hoop. He declares that he has "pulled a Homer".