Short clergyman for page three, say? (5)
I believe the answer is:
recto
'page three say?' is the definition.
(recto means the right-hand page of a book)
'short clergyman' is the wordplay.
'short' means to remove the last letter.
'clergyman' becomes 'rector' (rector is a kind of clergyman).
'rector' with its final letter taken away is 'RECTO'.
'for' acts as a link.
(Other definitions for recto that I've seen before include "one side" , "right page" , "The right-hand page or leaf of a book" , "front page" , "No leaves left" .)