Plain Gucci sable clothes making a comeback (5)
I believe the answer is:
basic
'plain' is the definition.
(thesaurus)
'gucci sable clothes making a comeback' is the wordplay.
'clothes' indicates a hidden word (the letters clothe the hidden word).
'making a comeback' shows that the letters should be reversed in order.
'cisab' can be found hidden inside 'gucci sable'.
'cisab' backwards is 'BASIC'.
(Other definitions for basic that I've seen before include "Without frills" , "No-frills" , "At the lowest level" , "Staple; ordinary" , "Simple, unadorned" .)