“Did I invite you to my barbecue? No! Then why are you all up in my grill?”

Entry in progress—B.P.
 
Urban Dictionary
grill
1. One’s personal business
2. One’s teeth/smile
Why you all up in my grill, fool?
(...)
by Yebeka December 19, 1999
   
Using English
Re: Why you all up in my grill?
calinative
26-Nov-2008, 02:06
My guess is that you like hip hop? Here’s my best at it.
 
The phrases are synonymous. But remember a “grill” is what you barbecue food on. So saying, “Why you all up in my grill,” may literally mean, “Why are you all over my food that I am grilling,” or like you said, “Why are you meddling in my affairs.”
 
Regarding being in someone’s face, it means confrontation. When people fight, they usually face off. Part of the body language people use to show they want to fight is to put their face right in front of the other person’s face.
 
With the above said, you might already know the answer to your other question about “Why you all up in my grill when you haven’t been invited to the barbeque?” This might be taken literally as, “Why are you tying to eat my food, when I didn’t invite you to the barbecue,” or “Why you messing in my personal affairs when you were not invited to my party?”
   
Twitter
Rosemarie
‏@invisiblehands
Joke o’ the day: Did i invite you to my barbeque? Then why are you all up in my grill?- http://ahelpinghand.ning.com
6:21 PM - 22 Jan 2009
 
Twitter
Mara Dixon
‏@maradixon
Did I invited you to my barbecue? ...no. Then why you all up in my grill?
10:17 PM - 28 Aug 2009
 
Twitter
gone girl
‏@umalright
i did not invite you to my barbecue so i do not know why you’re all up in my grill.
9:08 PM - 29 Aug 2009