look up any word, like cunt:
 
1.
To the most extreme degree.
I'm hungry as balls!
It's hot as balls in here!
That show was loud as balls.
by dokkus August 21, 2005
 
2.
A phrase added after any adjective to make it stronger.

Perhaps started by people trying to be less vulgar than using "as fuck" or "as shit", but still wanting to use a dirty word.

The resulting phrase doesn't have to have anything to do with testicles or their qualities; it's almost better when it's very un-ball-like, because it makes other people stop and think how your phrase doesn't make sense.
I'm hungry as balls!
Dude, your mom is hot as balls.
I was sick as balls last night.
It's cold as balls out here!
It's cold as balls are not!
by Coell June 12, 2006