hol'low bak (?) n. - An advanced freeze in bboying where the torso and legs are held aloft with the only points of the body touching the ground being the back of the head and both hands.

After performing some jaw-dropping uprock and floorwork, a bboy(or bgirl) might want to catch his (or her) breath for a bit by doing a freeze. Instead of just doing an everyday "baby" freeze, the dancer might may go the extra mile and melt the minds of the audience by doing a hollow back.

The positioning is a little difficult to explain, and even more difficult to perform. To begin with, I suggest that you use a wall to prop yourself up against or perhaps have a friend on hand to steady your feet. Kneel down about two to three feet away from the wall (or friend), facing towards it. Lower your head to the floor and extend your arms above your head (like the Y in YMCA). Now, here's the tricky part. Simultaneously raise you hips in the air and push your head under your body away from the wall. Kick your feet over your body so they can rest on the wall.

Your chin should be planted in your chest with the top of your dome supporting most of the weight of your body. The rest of the weight should be distributed on your arms. Your arms should be extended straight behind your head. Your back should be extremely arched with your legs dangling almost at vertical.

The result looks somewhat similar to the vrikschika-asana yoga position (also called the Scorpion Posture), except the head is arching in the opposite direction.
Needless to say, this freeze takes an extreme amount of flexibility and strength in the shoulders, back and abs.

While you can do this move easily during practice when you have people to hold your legs or a wall to prop up against, it is infinitely harder to perform in the middle of a battle or show. So before you try to display your mad skills, be sure practice until you are comfortable with it.