Float Serve
A serve with little or no spin, so the ball drifts and dips on the way over. You toss it with almost no spin, contact the middle of the ball with a firm hand, and stop your arm instead of snapping your wrist. Once you add spin, it is no longer a float. Passers struggle with it for the same reason batters struggle with a knuckleball: the path changes late.
Example
The server tosses the ball high, contacts it, and stops her hand. The ball looks like it will land deep, then drops early in the back-left corner. The passer is still moving forward.
Frequently Asked Questions
How do you hit a float serve in volleyball?
Toss the ball with as little spin as you can, hit the center with a stiff wrist, and stop your hand at contact. The goal is no rotation. If you snap your wrist, you have turned it into a topspin serve.
Why does a float serve move so much?
A spinning ball has a stable axis, so the flight is smoother. A float has no spin, and the seams catch the air unevenly. That pushes the ball sideways or makes it drop. It is the same idea as a knuckleball.