annulus

2 definitions found

annulus - Collaborative International Dictionary of English v.0.48 :

  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]

annulus - WordNet (r) 2.1 (2005) :

  annulus
      n 1: a toroidal shape; "a ring of ships in the harbor"; "a halo
           of smoke" [syn: ring, halo, annulus, doughnut,
           anchor ring]
      2: (Fungi) a remnant of the partial veil that in mature
         mushrooms surrounds the stem like a collar [syn: annulus,
         skirt]