Bays but can be silent (6)
I believe the answer is:
inlets
'bays' is the definition.
(I've seen this in another clue)
'can be silent' is the wordplay.
'can be' indicates anagramming the letters.
'silent' with letters rearranged gives 'INLETS'.
'but' acts as a link.
(Other definitions for inlets that I've seen before include "Silent strips of water" , "Narrow channels of water running from sea or river" , "Small arms off larger bodies of water" , "Bays or coves" , "Small bays of silent kind" .)