-Same term as Rock On! Used to show appreciation for rock.
-Used for cheering at someone.
-Means that somebody does something completely to the limit.
Guy 1: ROCK IT OUT! ROCK IT OUT!
Girl 1: Look at Timmy playing guitar!
Girl 2: Rock it out, Jimmy!
Guy 1: How was your job interview?
Guy 2: Awesome. I completely rocked it out.