Another word to describe money, cash, bills, or guap. Used mostly when your wallet is overflowing with big bills.
Dude dinner is on me i got straight billies in my wallet
dude i just put in 50 hours last week, my wallet is gonna be full of billies
the term 'Billies' is short for Hillbillies. Very useful when you need to discuss without them catching on.
I'm going to Oklahoma tomorrow, there will be Billies everywhere.