Originating from a term referring to a very talented basketball player, typically a pro or from "street ball", who lives lavishly--this phrase is commonly used to refer now to anyone who likes to "live large"
Lebron James is a "Big Baller"
Puff Daddy is a "Big Baller" (and a shot caller)
50 cent and Kanye are "Big Ballers"
Fat Joe is a REALLY BIG Baller
Your mom is a "Big Baller"