The Collaborative International Dictionary of English v.0.48:

Sham \Sham\, v. t. [imp. & p. p. Shammed; p. pr. & vb. n.
   Shamming.]
   1. To trick; to cheat; to deceive or delude with false
      pretenses.
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            Fooled and shammed into a conviction. --L'Estrange.
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   2. To obtrude by fraud or imposition. [R.]
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            We must have a care that we do not . . . sham
            fallacies upon the world for current reason.
                                                  --L'Estrange.
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   3. To assume the manner and character of; to imitate; to ape;
      to feign.
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   To sham Abram or To sham Abraham, to feign sickness; to
      malinger. Hence a malingerer is called, in sailors' cant,
      Sham Abram, or Sham Abraham.
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The Collaborative International Dictionary of English v.0.48:

Sham \Sham\, v. i.
   To make false pretenses; to deceive; to feign; to impose.
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         Wondering . . . whether those who lectured him were
         such fools as they professed to be, or were only
         shamming.                                --Macaulay.
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The Collaborative International Dictionary of English v.0.48:

Sham \Sham\ (sh[a^]m), n. [Originally the same word as shame,
   hence, a disgrace, a trick. See Shame, n.]
   1. That which deceives expectation; any trick, fraud, or
      device that deludes and disappoints; a make-believe;
      delusion; imposture; humbug. "A mere sham." --Bp.
      Stillingfleet.
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            Believe who will the solemn sham, not I. --Addison.
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   2. A false front, or removable ornamental covering.
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   Pillow sham, a covering to be laid on a pillow.
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The Collaborative International Dictionary of English v.0.48:

Sham \Sham\, a.
   False; counterfeit; pretended; feigned; unreal; as, a sham
   fight.
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         They scorned the sham independence proffered to them by
         the Athenians.                           --Jowett
                                                  (Thucyd)
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WordNet (r) 3.0 (2006):

sham
    adj 1: adopted in order to deceive; "an assumed name"; "an
           assumed cheerfulness"; "a fictitious address"; "fictive
           sympathy"; "a pretended interest"; "a put-on childish
           voice"; "sham modesty" [syn: assumed, false,
           fictitious, fictive, pretended, put on, sham]
    n 1: something that is a counterfeit; not what it seems to be
         [syn: fake, sham, postiche]
    2: a person who makes deceitful pretenses [syn: imposter,
       impostor, pretender, fake, faker, fraud, sham,
       shammer, pseudo, pseud, role player]
    v 1: make a pretence of; "She assumed indifference, even though
         she was seething with anger"; "he feigned sleep" [syn:
         simulate, assume, sham, feign]
    2: make believe with the intent to deceive; "He feigned that he
       was ill"; "He shammed a headache" [syn: feign, sham,
       pretend, affect, dissemble]