Name again protected by secret? It leaks (7)
I believe the answer is:
retitle
'name again' is the definition.
('title' is an answer for 'name' so perhaps 'retitle' is OK for 'name again')
'protected by secret? it leaks' is the wordplay.
'protected by' says the answer is hidden in the clue.
'RETITLE' is hidden within 'secret it leaks'.
(Other definitions for retitle that I've seen before include "Give a new name to" , "name differently" , "Give a different name to (a book)" , "Call again on" , "Lit tree (anag)" .)