Disregard finished appearance (8)
I believe the answer is:
overlook
'disregard' is the definition.
(thesaurus)
'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 a fault or have a view from above" , "excuse" , "Give a view from above - miss" , "Disregard" , "Keep an eye on" .)