What is Butt Groove?
1.
The perma-dent in your favorite chair or sofa where you spend most of your leisure time; the result of too much leisure time spent in your favorite spot; the act of deepening the spot by doing nothing
you: " What are you doing this weekend?"
me: "Absolutely nothing, just working on my butt groove"
or
You: "how's that butt groove coming along?"
me: "great, I haven't moved an inch in hours."
See 
Random Words:
1. 
When you tell someone to "Fuck off and die!" and it comes out quickly! Often abbrieviated to FOAD
Nat: I HATE YOU!
Josh: Fuc..