Passionate about new and ostentatious clothes (6)
I believe the answer is:
finery
'ostentatious clothes' is the definition.
(I've seen this before)
'passionate about new' is the wordplay.
'passionate' becomes 'fiery' ('fiery' can be similar in meaning to 'passionate').
'about' indicates putting letters inside.
'new' becomes 'n'.
'fiery' going around 'n' is 'FINERY'.
'and' is the link.
(Other definitions for finery that I've seen before include "Fancy clothes or trappings" , "Ostentatious decoration" , "Ostentatious clothes" , "Elaborate clothes and accessories" , "Elaborate clothing, jewellery etc" .)