Fashionable before Windy City (7)
I believe the answer is:
chicago
'windy city' is the definition.
(Chicago is nicknamed the Windy City)
'fashionable before' is the wordplay.
'fashionable' becomes 'chic' (chic means stylish or fashionable).
'before' becomes 'ago' (eg years ago means year before).
'chic'+'ago'='CHICAGO'
(Other definitions for chicago that I've seen before include "Musical (in Illinois?)" , "Type of bridge" , "A Windy City in Illinois" , "3 city in the US" , "Port on Lake Michigan" .)