Douglas Harper's Etymology Dictionary
high-roller
"extravagant spender," by 1873, American English, probably originally a reference to a gambler throwing dice.
Wiktionary
high-roller
n. (alternative spelling of high roller English)
Usage examples of "high-roller".
Back in the casino, Ennis heard the dreary bleating of a keno machinesounded as if one of the high-rollers back there was temporarily a few dollars richer.
The Riviera, with its jet-setters and high-roller socialites, has been drug-dealer heaven for a long, long time.