Five not appearing in new season (4)
I believe the answer is:
noel
'season' is the definition.
(the Christmas season)
'five not appearing in new' is the wordplay.
'five' becomes 'v' (roman numeral).
'not appearing in' suggests deleting specific letters.
'new' becomes 'novel' (synonyms).
'novel' with 'v' taken away is 'NOEL'.
(Other definitions for noel that I've seen before include "Feature of last month" , "Christmas time" , "Xmas refrain" , "Lone male name" , "See 7 Across" .)