Got back a Roman garment (4)
I believe the answer is:
toga
'roman garment' is the definition.
(I've seen this in another clue)
'got back a' is the wordplay.
'back' says the letters should be written backwards.
'got' in reverse letter order is 'tog'.
'tog'+'a'='TOGA'
(Other definitions for toga that I've seen before include "Roman dress" , "Cloak of ancient Rome" , "Garment worn by men in ancient Rome" , "Roman raiment" , "garment of old" .)