Finish in attempt to be fashionable (6)
I believe the answer is:
trendy
'be fashionable' is the definition.
(similar in meaning)
'finish in attempt' is the wordplay.
'finish' becomes 'end' (synonyms).
'in' indicates putting letters inside.
'attempt' becomes 'try' (synonyms).
'end' inserted within 'try' is 'TRENDY'.
'to' is the link.
(Other definitions for trendy that I've seen before include "Cool" , "Modish" , "Consciously fashionable" , "With it, a la mode" , "In accordance with the latest fad" .)