Movement that's bound to be reported (4)
I believe the answer is:
tide
'movement' is the definition.
(I have seen 'Movement of seawater ' mean 'tide' so perhaps 'movement' could also mean 'tide')
'bound to be reported' is the wordplay.
'bound' becomes 'tied' (similar in meaning).
'to be reported' shows a homophone (sound like).
'tied' sounds like 'TIDE'.
'that's' is the link.
(Other definitions for tide that I've seen before include "Ebber and flower?" , "Periodic flow" , "Periodic water movement" , "Rising and falling of the sea" , "It ebbs and flows" .)