Distinctive, with rather large dresses (8)
I believe the answer is:
Here is my best explanation:
'distinctive' is the definition.
'with rather large dresses' is the wordplay.
'with' becomes 'and' (I've seen this before).
'rather large' becomes 'stout'.
'dresses' indicates putting letters inside (dress can mean cover).
'and' placed into 'stout' is 'STANDOUT'.
(Other definitions for standout that I've seen before include "Persist in opposing" and "project".)