Barber shop with no work to declare (6)
I believe the answer is:
shaver
'barber' is the definition.
(thesaurus)
'shop with no work to declare' is the wordplay.
'with no' suggests deleting specific letters.
'work' becomes 'op' (abbreviation for opus).
'to declare' becomes 'aver' (averring is a kind of declaring).
'shop' with 'op' removed is 'sh'.
'sh'+'aver'='SHAVER'
(Other definitions for shaver that I've seen before include "Hair remover" , "Young lad (dated); razor" , "A razor or its user" , "Electric razor" , "Youth" .)