False god lacking originality — not new (4)
I believe the answer is:
baal
'false god' is the definition.
(I've seen this in another clue)
'lacking originality not new' is the wordplay.
'lacking originality' becomes 'banal' (I've seen this before).
'not' suggests deleting specific letters.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'banal' with 'n' taken away is 'BAAL'.
(Other definitions for baal that I've seen before include "God Elijah defeated" , "Hellish idol" , "Fertility god (false to some)" , "alse god" , "Canaanite fertility god" .)