(n.) The weight gain and associated expansion of one's butt caused by the lack of physical activity induced by spending too much time surfing the internet once he has broadband internet access at his home.
Good god, have you seen Jim? He used to be so thin and athletic, but since he's gotten a cable modem he's been stricken by the worst case of broadband butt I've ever seen.
by Franz in HB May 24, 2006