Joe: Mike, I almost got hit by a car crossing Delaware Avenue while jogging.
Mel: Did I ever tell you about the time I almost got hit by a plane in Melbourne?
Mike: Mel, let him finish the story. Why do you gotta be such a trumper?
You meant to type in trumpet, but you were typing too fast and made a typo, which, in turn, led you to see the urban dictionary page. Now you find yourself here.
John typed too fast and spelled trumper. then he saw the word on urban dictionary and clicked on it.