Larry the Cable Guy on Blue Collar TV uses this as a sort of catchphrase. It's meaning is pretty much universal, but is mostly used as a way of agreeing with something enthusiastically.
Son: Hey Dad, do I plug in the leaf blower now?
Dad: GETERDONE!
Dude1: Dude, that chick is so hawt!
Dude2: GETERDONE!
no,no,no. You folksgot it all wrong. Trust me I was there when this happened. To deflower a young woman.
The girl wanted me to have sex with her friend. She shut the bedroom door and said," When she comes out of there I want her split like the Grand Canyon. Geterdone."
The ability girls and women have developed to hold several items at once in one hand. The skill has been developed due to the lack of pockets in women's clothing.
I thought she'd need multiple trips to carry her phone, keys, wallet, and Starbucks to her car since she needed the other hand to open the door, but she used her impressive girl grip to carry everything in one hand.