Nothing odd in Kennedy’s demise (3)
I believe the answer is:
end
'demise' is the definition.
(I've seen this in other clues)
'nothing odd in kennedy's' is the wordplay.
'nothing odd in' indicates alternate letters (only the letters in even-numbered positions).
The alternate letters of 'kennedy' are 'END'.
(Other definitions for end that I've seen before include "result" , "Intention" , "Extreme" , "Concluding purpose" , "Termination" .)