Miss finished appearance (8)
I believe the answer is:
overlook
'miss' is the definition.
(overlooking is a kind of missing)
'finished appearance' is the wordplay.
'finished' becomes 'over' ('over' can be similar in meaning to 'finished').
'appearance' becomes 'look' (look is a kind of appearance**).
'over'+'look'='OVERLOOK'
(Other definitions for overlook that I've seen before include "Ignore or fail to notice" , "Disregard" , "Fail to observe or decide to ignore" , "Ignore a fault or have a view from above" , "excuse" .)