The Collaborative International Dictionary of English v.0.48:

Swindler \Swin"dler\, n. [G. schwindler, fr. schwindlen to be
   dizzy, to act thoughtlessly, to cheat, fr. schwindel
   dizziness, fr. schwinden to vanish, to disappear, to dwindle.
   See Swim to be dizzy.]
   One who swindles, or defrauds grossly; one who makes a
   practice of defrauding others by imposition or deliberate
   artifice; a cheat.
   [1913 Webster]

   Syn: Sharper; rogue.

   Usage: Swindler, Sharper. These words agree in describing
          persons who take unfair advantages. A swindler is one
          who obtains money or goods under false pretenses. A
          sharper is one who cheats by sharp practice, as in
          playing at cards or staking what he can not pay.
          [1913 Webster]

                Fraud and injustice soon follow, and the dignity
                of the British merchant is sunk in the
                scandalous appellation of a swindler. --V. Knox.
          [1913 Webster]

                Perhaps you 'll think I act the same
                As a sly sharper plays his game.  --Cotton.
          [1913 Webster]

WordNet (r) 3.0 (2006):

swindler
    n 1: a person who swindles you by means of deception or fraud
         [syn: swindler, defrauder, chiseller, chiseler,
         gouger, scammer, grifter]