The Collaborative International Dictionary of English v.0.48:

Skim \Skim\ (sk[i^]m), v. t. [imp. & p. p. Skimmed (sk[i^]md);
   p. pr. & vb. n. Skimming.] [Cf. Sw. skymma to darken.
   [root]158. See Scum.]
   1. To clear (a liquid) from scum or substance floating or
      lying thereon, by means of a utensil that passes just
      beneath the surface; as, to skim milk; to skim broth.
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   2. To take off by skimming; as, to skim cream.
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   3. To pass near the surface of; to brush the surface of; to
      glide swiftly along the surface of.
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            Homer describes Mercury as flinging himself from the
            top of Olympus, and skimming the surface of the
            ocean.                                --Hazlitt.
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   4. Fig.: To read or examine superficially and rapidly, in
      order to cull the principal facts or thoughts; as, to skim
      a book or a newspaper.
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The Collaborative International Dictionary of English v.0.48:

Skimming \Skim"ming\, n.
   1. The act of one who skims.
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   2. That which is skimmed from the surface of a liquid; --
      chiefly used in the plural; as, the skimmings of broth.
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WordNet (r) 3.0 (2006):

skimming
    n 1: the act of removing floating material from the surface of a
         liquid
    2: reading or glancing through quickly [syn: skim, skimming]
    3: failure to declare income in order to avoid paying taxes on
       it
    4: the act of brushing against while passing [syn: grazing,
       shaving, skimming]