Think again about what’s the correct short title for a vicar? (7)
I believe the answer is:
revisit
'think again about' is the definition.
(revisit can mean to re-examine something)
'the correct short title for a vicar?' is the wordplay.
'the correct short title' becomes 'isit' (I can't justify this - if you can you should believe this answer much more).
'for' is a charade indicator (letters next to each other) (I've seen this in other clues).
'a vicar?' becomes 'rev' (reverend).
'isit' after 'rev' is 'REVISIT'.
'what's' acts as a link.
(Other definitions for revisit that I've seen before include "comeback?" , "Go back to (place)" , "Reconsider" , "Pay further call" , "Consider again" .)