Yankee priest right to rabbit on (6)
I believe the answer is:
yabber
'rabbit on' is the definition.
(I've seen this before)
'yankee priest right' is the wordplay.
'yankee' becomes 'Y' (phonetic alphabet: alpha, bravo, charlie etc.).
'priest' becomes 'abbe' (I've seen this before).
'right' becomes 'r' (common abbreviation).
'y'+'abbe'+'r'='YABBER'
'to' acts as a link.
(Other definitions for yabber that I've seen before include "Chatter" , "Conversation in Sydney" , "rabbit on" .)