Answer by friend upset cleric, causing fuss (7)
I believe the answer is:
'fuss' is the definition.
(I've seen this before)
'answer by friend upset cleric' is the wordplay.
'answer' becomes 'a' (abbreviation eg in Q and A).
'by' means one lot of letters go next to another.
'friend' becomes 'pal' (pal is a kind of friend).
'upset' shows that the letters should be reversed in order.
'cleric' becomes 'Rev' (abbreviation for Reverend).
'rev' reversed gives 'ver'.
'a' after 'pal' is 'pala'.
'causing' acts as a link.
(Other definitions for palaver that I've seen before include "Powwow - a lot of fuss", "Song and dance", "Long tedious fuss", "Fuss and bother", "Hubbub; lengthy fuss".)