Passion is more extreme in EastEnders (7)
I believe the answer is:
fervour
'passion' is the definition.
(fervour is a kind of passion)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for fervour that I've seen before include "Great enthusiasm" , "Vehemence" , "Heated feeling" , "Heat of emotion" , "Ardent intensity" .)