to·rus 
(tôrəs)
(tôrəs)n. pl. to·ri (tôrī)
1. Architecture A large convex molding, semicircular in cross section, located at the base of a classical column.
2. Anatomy A bulging or rounded projection or swelling.
3. Botany
a. The receptacle of a flower.
b. A thickened area in the middle of the membrane that connects the pits of tracheids in conifers and certain other gymnosperms.
4. Mathematics A toroid generated by a circle; a surface having the shape of a doughnut. Also called tore2.
[Latin, bulge, knot, torus.]
torus