shoplifter

from WordNet (r) 3.0 (2006)

shoplifter
    n 1: a thief who steals goods that are in a store [syn:
         {booster}, {shoplifter}, {lifter}]

from The Collaborative International Dictionary of English v.0.48

Shoplifter \Shop"lift`er\, n. [Shop + lift. See {Lift} to
   steal.]
   One who steals anything in a shop, or takes goods privately
   from a shop; one who, under pretense of buying goods, takes
   occasion to steal.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

32 Moby Thesaurus words for "shoplifter":
      body snatcher, booster, chicken thief, con man, crook,
      den of thieves, embezzler, filcher, ganef, ghoul, grafter,
      grave robber, jewel thief, land pirate, land shark, land-grabber,
      larcener, larcenist, lifter, peculator, petty thief, pilferer,
      poacher, prowler, purloiner, robber, scrounger, sneak thief,
      stealer, swindler, thief, white-collar thief

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