Bohemian tart after joint (6)
I believe the answer is:
hippie
'bohemian' is the definition.
(thesaurus)
'tart after joint' is the wordplay.
'tart' becomes 'pie' (I've seen this before).
'after' means one lot of letters go next to another.
'joint' becomes 'hip' (hip is a kind of joint**).
'pie' put after 'hip' is 'HIPPIE'.
(Other definitions for hippie that I've seen before include "Sixties rebel" , "1960s' dropout" , "Flower child" , "Sixties youth" , "60s dropout" .)