What is "annuli"

Annulus \An"nu*lus\, n.; pl. Annuli. [L.]

1. A ring; a ringlike part or space.

2. (Geom.)

   1. A space contained between the circumferences of two circles, one within the other.

   2. The solid formed by a circle revolving around a line which is the plane of the circle but does not cut it.

3. (Zo["o]l.) Ring-shaped structures or markings, found in, or upon, various animals.

n. (en-irregular plural of: annulus)

1. n. a toroidal shape; "a ring of ships in the harbor"; "a halo of smoke" [syn: ring, halo, anulus, doughnut, anchor ring]

2. (Fungi) remnant of the partial veil that in mature mushrooms surrounds the lower part of the stem

3. [also: annuli (pl)]

See annulus