Sneak thief (10)
(Other definitions for pickpocket that I've seen before include "Cutpurse" , "Dip" , "Tea leaf" , "Artful Dodger?" , "Thief working in public places" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sneak thief</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for pilferer that I've seen before include "Thief who steals in small quantities" , "One stealing small items" , "A thief of small items as from shops" , "Petty thief" .)