Annulus vs Toroid - What's the difference?
annulus | toroid |
A ring- or donut-shaped area or structure.
(geometry) The region in a plane between two concentric circles of different radius.
(topology) Any topological space homeomorphic to the region in a plane between two concentric circles of different radius.
(astronomy) The ring of the sun not covered by the moon in an annular solar eclipse.
(botany) Structure in a fern that consists of differentially thick-walled cells on a sporangium that bend and distort as a result of drying.
(mycology) The membranous remnants of a partial veil which leaves a ring on the stem of a mushroom.
(oil and gas production) The space contained between the centre well bore and any external tubing. Sometimes used for separated gas flow.
(mathematics) A surface generated by a closed curve (especially a circle) rotating about, but not intersecting or containing, an axis in its own plane.
A ring-shaped object whose surface is a torus.