Very small object in your trousers (4)
I believe the answer is:
tiny
'very small' is the definition.
(I've seen this in another clue)
'object in your trousers' is the wordplay.
'trousers' indicates the answer is hidden within the clue (trouser can mean to steal or take).
'TINY' is hidden in the letters of 'object in your'.
(Other definitions for tiny that I've seen before include "Miniscule" , "Little" , "Minute, diminutive" , "Wee" , "Quite insignificant" .)