Replacement cardinal? (6)
I believe the answer is:
newman
'replacement cardinal?' is the definition.
'newman' can be an answer for 'cardinal?' (19th-century Cardinal John Newman). I'm not sure about the 'replacement' bit.
'replacement cardinal?' is the wordplay.
'replacement' becomes 'new'.
'cardinal?' becomes 'man' (I am not sure about this - if you are sure you should believe this answer much more).
'new'+'man'='NEWMAN'
Can you help me to learn more?
(Other definitions for newman that I've seen before include "Paul -, US actor" , "Cardinal - PC husband" , "John Henry --, beatified English theologian" , "John Henry --, beatified English cardinal" , "Cardinal -- Paul, actor" .)