Hoop
Sports Dictionary
Albert Einstein: "The most incomprehensible thing in this world is that it is comprehensible."
– a sports apparatus used in women's artistic gymnastics. The hoop is a torus-shaped object made of plastic, PVC, or polyethylene (previously made of wood). The diameter of the hoop depends on the height of the gymnast and is 70-90 cm. The apparatus can be solid-colored or multi-colored, and gymnasts sometimes decorate it with colored tape. 
Related to terms that indicate sports apparatus
Other definitions in the section "Gymnastics terms"
Albert Einstein: "The most incomprehensible thing in this world is that it is comprehensible."