Clown's a hit, with trendy greeting in EastEnders? (11)
I believe the answer is:
punchinello
'clown's' is the definition.
(I've seen this before)
'a hit with trendy greeting in eastenders?' is the wordplay.
'a hit' becomes 'punch' (I've seen this before).
'with' means one lot of letters go next to another.
'trendy' becomes 'in' ('in' can mean fashionable).
'greeting in eastenders?' becomes 'ello' (Cockney or East End pronunciation of 'hello').
'punch'+'in'+'ello'='PUNCHINELLO'
(Other definitions for punchinello that I've seen before include "buffoon" , "Clown" .)