Restore confidence (8)
I believe the answer is:
reassure
'restore confidence' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reassure that I've seen before include "Comfort, convince again" , "calm fears" , "Restore confidence about erasures" , "Allay fears of (someone)" , "Relieve (someone) of anxieties" .)