Refers to a member of the opposite sex who, although acceptable for a one-night stand, is not worthy of being taken out to dinner or meeting your family.
Erik: Why didn't you get that bartender's digits? Take her out some time.
B-Rad: Oh her? That Ain't No Dinner Thing.
Another way to say that something doesn't fit a person, doesn't suit them, or isn't met for them. Commonly pronounced as "ain't 'bout dat life."
Sarah is so hot for Dave that she is acting like she's easy to get his attention, but she ain't about that life.
That geek Bill Nye watched way too much Breaking Bad and now he's trying to find a partner to cook meth with. We all know he ain't 'bout dat life.
She was talking shit about my best friend, so i punched her in the face instead of talking shit. I ain't fake, I ain't 'bout dat life.
Twin 1: "hey friend my girlfriend just dumped me."
Friend: "i'm sorry, who did she leave you for?"
Twin 2: "Me!"
Friend: "Well, ain't that a kick in the dick?"