annulus

Noun
Synonyms: ringhalodoughnutanchor ringskirt

WordNet 3.0

Noun (2)

  1. a toroidal shape“a ring of ships in the harbor”“a halo of smoke”Synonyms: ringhalodoughnutanchor ring
  2. (Fungi) a remnant of the partial veil that in mature mushrooms surrounds the stem like a collarSynonyms: skirt
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Webster's Dictionary (GCIDE)

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

1.A ring; a ringlike part or space. [1913 Webster]

2.(Geom.) (a) A space contained between the circumferences of two circles, one within the other. (b) The solid formed by a circle revolving around a line which is the plane of the circle but does not cut it. [1913 Webster]

3.(Zool.) Ring-shaped structures or markings, found in, or upon, various animals. [1913 Webster]

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