Duck has to desist taking ring (5)
I believe the answer is:
stoop
'duck' is the definition.
(thesaurus)
'to desist taking ring' is the wordplay.
'to desist' becomes 'stop' (I've seen this before).
'taking' is an insertion indicator.
'ring' becomes 'o' (letter resembling a ring).
'stop' going around 'o' is 'STOOP'.
'has' acts as a link.
(Other definitions for stoop that I've seen before include "Lean forward" , "Condescend" , "Sink" , "Stand bent forward" , "Crouch" .)