A person in society that has a better grasp of the world, is a little brighter than the next person and has a pocket full of cash. Women typically love these kinds of men.
It may also be used as a verb as a term for agression.
Look at him pulling up in his BMW, he must be a highroller. I'm gonna give him some head(see head in dictionary).
I'm about to highroll that nigga.
A “High Roller” is someone who spends lots of money carelessly, blowing money fast and recklessly. The termoriginated from high stakes players who place large bets at the casino.