The Collaborative International Dictionary of English v.0.48:

Idol \I"dol\, n. [OE. idole, F. idole, L. idolum, fr. Gr. ?, fr.
   ? that which is seen, the form, shape, figure, fr. ? to see.
   See Wit, and cf. Eidolon.]
   1. An image or representation of anything. [Obs.]
      [1913 Webster]

            Do her adore with sacred reverence,
            As th' idol of her maker's great magnificence.
                                                  --Spenser.
      [1913 Webster]

   2. An image of a divinity; a representation or symbol of a
      deity or any other being or thing, made or used as an
      object of worship; a similitude of a false god.
      [1913 Webster]

            That they should not worship devils, and idols of
            gold.                                 --Rev. ix. 20.
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   3. That on which the affections are strongly (often
      excessively) set; an object of passionate devotion; a
      person or thing greatly loved or adored.
      [1913 Webster]

            The soldier's god and people's idol.  --Denham.
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   4. A false notion or conception; a fallacy. --Bacon.
      [1913 Webster]

            The idols of preconceived opinion.    --Coleridge.
      [1913 Webster]

WordNet (r) 3.0 (2006):

idol
    n 1: a material effigy that is worshipped; "thou shalt not make
         unto thee any graven image"; "money was his god" [syn:
         idol, graven image, god]
    2: someone who is adored blindly and excessively [syn: idol,
       matinee idol]
    3: an ideal instance; a perfect embodiment of a concept [syn:
       paragon, idol, perfection, beau ideal]

The Free On-line Dictionary of Computing (19 January 2023):

IDOL

   Icon-Derived Object Language.  An object-oriented
   preprocessor for Icon.

   (ftp://src.doc.ic.ac.uk/pub/languages/icon/idol.tar.Z).

   ["Programming in Idol: An Object Primer", C.L. Jeffery, U
   Arizona CS TR #90-10].