An annulus is a two-dimensional shape which can be thought of as a disc with a smaller disc removed from its center. An annulus looks like:

Note that both the inner and outer radii may take on any values, so long as the outer radius is larger than the inner.

Title annulus
Canonical name Annulus
Date of creation 2013-03-22 12:26:23
Last modified on 2013-03-22 12:26:23
Owner akrowne (2)
Last modified by akrowne (2)
Numerical id 12
Author akrowne (2)
Entry type Definition
Classification msc 51-00