'Literature' now normally includes celebrity (6)
I believe the answer is:
renown
'celebrity' is the definition.
(synonyms)
'literature now normally includes' is the wordplay.
'includes' indicates a hidden word.
'RENOWN' can be found hidden inside 'literature now normally'.
(Other definitions for renown that I've seen before include "High reputation, fame" , "Fame and eminence" , "Plane's maximum width" , "High repute" , "Fame and public acclamation" .)