Definition of: torus

(tôr′əs, tō′rəs) noun plural to·ri (tôr′ī, tō′rī)
1. Archit. A large convex molding, nearly semicircular in cross–section: used in bases as the lowest molding, or in columns above the plinth.
2. Anat. A rounded ridge, as on the occipital bone of the skull.
3. Bot. The swollen end of a flowerstalk which bears the floral leaves; the receptacle.
4. Geom. The surface or solid generated by the rotation of a conic section about an axis in its own plane. [<L, lit., a swelling]