speculum

2 definitions found

speculum - Collaborative International Dictionary of English v.0.48 :

  Speculum \Spec"u*lum\, n.; pl. L. Specula, E. Speculum. [L.,
     fr. specere to look, behold. See Spy.]
     1. A mirror, or looking-glass; especially, a metal mirror, as
        in Greek and Roman archaeology.
        [1913 Webster]
  
     2. A reflector of polished metal, especially one used in
        reflecting telescopes. See Speculum metal, below.
        [1913 Webster]
  
     3. (Surg.) An instrument for dilating certain passages of the
        body, and throwing light within them, thus facilitating
        examination or surgical operations.
        [1913 Webster]
  
     4. (Zool.) A bright and lustrous patch of color found on the
        wings of ducks and some other birds. It is usually
        situated on the distal portions of the secondary quills,
        and is much more brilliant in the adult male than in the
        female.
        [1913 Webster]
  
     Speculum metal, a hard, brittle alloy used for making the
        reflectors of telescopes and other instruments, usually
        consisting of copper and tin in various proportions, one
        of the best being that in which there are 126.4 parts of
        copper to 58.9 parts of tin, with sometimes a small
        proportion of arsenic, antimony, or zinc added to improve
        the whiteness.
        [1913 Webster]

speculum - WordNet (r) 2.1 (2005) :

  speculum
      n 1: a mirror (especially one made of polished metal) for use in
           an optical instrument
      2: a medical instrument for dilating a bodily passage or cavity
         in order to examine the interior