grandma panties 

the huge saggy underwear, that your grandma, mom, or even you wear.

my grandma was wearing her grandma panties to the store.

grandma panties by swimmy761 January 1, 2004

empty as your grandma's panties 

To be out of money; when one's wallet is void of currency.

Aaron: Hey Brian, you want me to get you a Cherry-Pepsi?
Brian: Sorry bud, check out my wallet...it's as empty as your Grandma's panties.

empty as your grandma's panties by Hoon35 May 24, 2006