Jack’s approval, quietly overlooked (5)
I believe the answer is:
raise
'jack's' is the definition.
(I've seen this before)
'approval quietly overlooked' is the wordplay.
'approval' becomes 'praise' (praise is a kind of approval).
'quietly' becomes 'p' (p for piano and quiet).
'overlooked' suggests deleting specific letters.
'praise' with 'p' taken out is 'RAISE'.
(Other definitions for raise that I've seen before include "Call up" , "Care for during childhood" , "Lift; (to) levy (money)" , "Lift up, bring up" , "Bring up - an increase in pay" .)