Title of singer-sailor making a comeback (7)
I believe the answer is:
baronet
'title' is the definition.
(I've seen this before)
'singer-sailor making a comeback' is the wordplay.
'singer' becomes 'tenor' (tenor is a kind of singer).
'sailor' becomes 'ab' (abbreviation for able seaman).
'making a comeback' says the letters should be written backwards.
'tenor'+'ab'='tenorab'
'tenorab' written backwards gives 'BARONET'.
'of' acts as a link.
(Other definitions for baronet that I've seen before include "Lowest British hereditary title" , "Sir Somebody-or-other?" , "Minor title" , "Titled man" , "A Breton could be a British peer" .)