A common euphemism a girl may use for the act of fingering herself. Similarly, "painting her nails red" can sometimes refer to a girl fingering said cooter whilst she is menstruating.
guy #1: "So what's Sally up to tonight? Is she gonna chill with us?"
guy #2: "She said she's just staying in and painting her nails tonight. How fuckin' boring is that."
guy #1: "This is like the 3rd time this week she's blown us off to paint her nails, how many times does one person need to paint their nails?"
Used to describe the 'job' of a woman who leaves all the breadwinning to her partner, so instead has 'occupation' of sitting home and enjoying the comfort of doing nothing. The term derives from what women apparently love doing best as their pastime.
"He goes out and works his butt off while she sits at home, painting her nails"
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"