Suitable for evening wear (6)
I believe the answer is:
dressy
'suitable for evening wear' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for dressy that I've seen before include "Smartly clothed" , "swish" , "Wearing stylish clothes, elegant (6)" , "Liking to wear fancy or formal clothes" , "Smartly attired, wearing stylish clothes" .)