What comes to mind is: To move quickly and surreptitiously. Maybe he was sneaking around the end of the stall, trying not to be seen.

The verb is "duck", meaning to lower one's head to avoid being struck. The word "around" is a preposition.

"He moved quietly and quickly." It is assumed he did not want to be seen. You could also use if to mean quickly. "Duck around the corner and see if you can see them coming." - It is not a secret here. It can also be used just to go someplace for just short while, possibly with the implication that you don't want somebody to know, but not always. "Let's duck around to the pub and have a drink." Anytime you duck, you are usually doing so to avoid being seen or avoid being hit by something. In this case, it is the image that counts.