Wordnet 3.0
NOUN (1)
1. 
 a criminal who takes property belonging to someone else with the intention of keeping it or selling it; 
[syn: thief, stealer]
The Collaborative International Dictionary of English v.0.48:
Stealer \Steal"er\ (-[~e]r), n.
   1. One who steals; a thief.
      [1913 Webster]
   2. (Shipbuilding) The endmost plank of a strake which stops
      short of the stem or stern.
      [1913 Webster]
WordNet (r) 3.0 (2006):
stealer
    n 1: a criminal who takes property belonging to someone else
         with the intention of keeping it or selling it [syn:
         thief, stealer]