Pay attention to silent movement (6)
I believe the answer is:
listen
'pay attention to' is the definition.
(thesaurus)
'silent movement' is the wordplay.
'movement' is an anagram indicator.
'silent' anagrammed gives 'LISTEN'.
(Other definitions for listen that I've seen before include "Hark!" , "Pay heed (to advice)" , "Take heed -- 13 (anag)" , "Pay attention and hear" , "what buggers do" .)