Shy Matt emptied pockets (7)
I believe the answer is:
attempt
'shy' is the definition.
(thesaurus)
'matt emptied pockets' is the wordplay.
'pockets' indicates the answer is hidden within the clue (pocket can mean to contain).
'ATTEMPT' is hidden in the letters of 'matt emptied'.
(Other definitions for attempt that I've seen before include "Essay" , "Shot" , "Embark on, try" , "Endeavor, try" , "Try, endeavour" .)