Desire to take part in chit-chat (4)
I believe the answer is:
itch
'desire' is the definition.
(I know that itch is a type of desire)
'part in chit-chat' is the wordplay.
'part in' says the answer is hidden in the clue.
'ITCH' is hidden in the letters of 'chit chat'.
'to take' is the link.
(Other definitions for itch that I've seen before include "Impatient desire (colloq.)" , "Tickling sensation of skin" , "It must be scratched" , "Feel tingling sensation in skin" , "Tingle" .)