magnate

If you’re a hugely successful businessperson, particularly if you’ve cornered the market in a specific area, you’re a magnate. Magnates are often larger-than-life characters, like that oil tycoon who wears a cowboy hat with his tuxedo.

Historically, a magnate was a man of noble birth (from the Latin magnus, meaning "a nobleman," or at least someone distinguished by his achievements. In the twentieth century, the stock of a magnate has rather fallen. If you’re vulgar and loud-spoken as well as rich, you’re probably a magnate. Thanks to the legendary movie producer Samuel Goldwyn, all film studio heads are now "studio magnates."