Swinger having choice about dancing nude (8)
I believe the answer is:
pendulum
'swinger' is the definition.
(something which swings)
'choice about dancing nude' is the wordplay.
'choice' becomes 'plum' (both can mean excellent).
'about' indicates putting letters inside.
'dancing' indicates an anagram.
'nude' with letters rearranged gives 'endu'.
'plum' enclosing 'endu' is 'PENDULUM'.
'having' acts as a link.
(Other definitions for pendulum that I've seen before include "Swinging weight that regulates clock" , "It swings from side to side - in a clock?" , "Oscillating part of clock" , "Oscillating mechanism" , "Moves to and fro" .)