Some contraband, an antiquarian handkerchief (7)
I believe the answer is:
bandana
'handkerchief' is the definition.
(bandana is a kind of handkerchief)
'some contraband an antiquarian' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'BANDANA' can be found hidden inside 'contraband an antiquarian'.
(Other definitions for bandana that I've seen before include "Coloured square for wearing" , "Large and brightly coloured handkerchief" , "Brightly coloured neckerchief" , "Handkerchief worn round the head or neck" , "Large coloured neckerchief" .)