Exclusive shop design (4)
I believe the answer is:
posh
'exclusive' is the definition.
(thesaurus)
'shop design' is the wordplay.
'design' indicates anagramming the letters.
'shop' with letters rearranged gives 'POSH'.
(Other definitions for posh that I've seen before include "Upper-class - Spice girl" , "'opulent'" , "Upmarket" , "Mrs 4 across (colloq.)" , "Elegant, stylish" .)