Fashionable joint (3)
I believe the answer is:
hip
This clue is a double definition.
'fashionable' is the first definition.
(hip can mean trendy or fashionable)
'joint?' is the second definition.
(part of body)
(Other definitions for hip that I've seen before include "it can nowadays be replaced" , "Fruit of the wild rose (3)" , "Fashionable" , "Fruit of a rose plant" , "Trendy or stylish, like fruit of the wild rose" .)