Nanny up is a Gullah Geechee term that means to defecate, shit, poop, or to go number two. It’s mostly used when a child needs a diaper changed, but also if someone has used the restroom and has left a lingering odor.
Liz: So how was Raj's visit last night? Did you guys go all the way?
Stacey: Nah, I didn't wanna go that far so we just did an Upside-Down Nancy and called it a night. I had a lot of fun though!
Nephew: *cough* prude *cough*