What is Backing?
1.
To support something.
I am backing the new Muse album.
2.
When you need to go somewhere for whatever reason, and you don't want to be there on your own, so you get a few (or one) of your friends to come with you so it looks like you have friends.
Hey man, I need to go to the bowling alley, can you be my backing?
See 
3.
(Uk Slang)
To back is to aquire.
Blood, dem trainers are live, I'm gonna back a pair.
Lee did you remember to back your car keys?
Random Words:
1. 
tall skinny kid with a dent in his chest. has a very loving father who cares for him, but leaves his empty beer cans in the back of kolb.. 
1. 
Yiddish: A lame, ineffectual, or pussy-whipped woman of a man.
I can't take that schmageggy seriously while he's gesticulatin..