Learning a new role (4)
I believe the answer is:
lore
'learning' is the definition.
(both can mean tradition or knowledge)
'a new role' is the wordplay.
'a new' indicates an anagram.
'role' anagrammed gives 'LORE'.
(Other definitions for lore that I've seen before include "Mythology" , "Ancient learning" , "Folk myths" , "Traditional belief" , "Wisdom" .)