Blanket is finished completely (7)
I believe the answer is:
overall
'blanket' is the definition.
(I've seen this before)
'finished completely' is the wordplay.
'finished' becomes 'over' (over can mean finished or ended).
'completely' becomes 'all' (synonyms).
'over'+'all'='OVERALL'
'is' is the link.
(Other definitions for overall that I've seen before include "generally speaking" , "Omnipotent" , "In total" , "Protective cover for worker" , "sweeping?" .)