Mean to alter heading (4)
I believe the answer is:
name
'heading' is the definition.
'mean to alter' is the wordplay.
'to alter' indicates an anagram.
'mean' with letters rearranged gives 'NAME'.
(Other definitions for name that I've seen before include "Handel, for example" , "Amen (anag)" , "Appoint - famous person" , "''A rose by any other ... would smell as sweet'' (Romeo and Juliet)" , "Designation; fame" .)