Frisbees and Boomerangs are heavier-than-air, unpowered, and fly through the air. So are they technically gliders?
They also rotate, so I wonder if these are actually some kind of rotorcraft-type gliders. I looked up all types of rotorcraft on wikipedia, which listed 4 things: helicopters, auto-gyros, gyrodynes, and cyclocopters. All of them were powered, so none of them were rotor-gliders. But then, auto-rotation in a helicopter might be considered gliding (with a pretty bad glide ratio).
One reason I ask is because I want to try to figure out the glide ratio or lift-to-drag ratio of these weird things. Not so easy to do empirically for a boomerang since it takes a weird ascending and descending path. How would you calculate that for a rotating assymetric airfoil?