Similar to short man syndrome. Except the bearer of this awful title doesn't have to be short, stubby, vertically challenged or petite. Although short dicked is a common trait. And obviously angry. Usually at the world for getting dealt the short hand, or in this case the Sundance hand. He walks around with his face all red, his chest puffed out, and a chip on his shoulder. With a name like Sundance who can blame him?
Who's thatparty pooperover there all pissed off taking all the candy from those kids? He's acing like he has Sundance man syndrome.
Whats your friend's name? Moonwalker? Sunscreen? Sunburn? Sun of a bitch? Ohhhh!!! Duh! Sundance! Who could forget that? Silly me!
Big Man Syndrome (BMS) is marked by delusions that because there's a girl willing to sleep with you and hang on your every word (hence being a "big man") that everyone else, particularly males, are equally enthusiastic supporters of the mindless bullshit you purport. Other symptoms include: unwillingness to listen or compromise, unreasonable demands you expect to be fulfilled and the belief everyone else shares your interests.