Thief pilfers hot pants (10)
I believe the answer is:
shoplifter
'thief' is the definition.
(shoplifter is a kind of thief)
'pilfers hot pants' is the wordplay.
'pants' indicates an anagram (UK informal term for 'nonsense' or 'rubbish').
'pilfers'+'hot'='pilfershot'
'pilfershot' with letters rearranged gives 'SHOPLIFTER'.
(Other definitions for shoplifter that I've seen before include "A petty criminal" , "guilty party" , "Robber" , "Thief" , "Thieving customer" .)