Purloiner (5)
I believe the answer is:
thief
'purloiner' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for thief that I've seen before include "Burglar, say" , "One with taking ways" , "Unlawful taker" , "A robber or pickpocket" , "'Taffy was a - - '" .)