A toy in the form of a large hoop which is twirled around various parts of the body, especially the waist.
To use a hula hoop.
A ring-shaped object, especially a large ring-shaped chamber used in physical research.
The thickening of a membrane closing a wood-cell pit (as of gymnosperm tracheids) having the secondary cell wall arched over the pit cavity.
A rounded ridge of bone or muscle, especially one on the occipital bone.
{{lb|en|topology|in combination|n-torus|4-torus|etc.}} The product of the specified number of circles.
A topological space which is a product of two circles.
A large convex molding, typically semicircular in cross section, which commonly projects at the base of a column and above the plinth.
The end of the peduncle or flower stalk to which the floral parts (or in the Asteraceae, the florets of a flower head) are attached.