Covering some Israeli dissidents (3)
I believe the answer is:
lid
'covering' is the definition.
(lid is a kind of covering)
'some israeli dissidents' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'LID' can be found hidden inside 'israeli dissidents'.
(Other definitions for lid that I've seen before include "Removable top" , "Hinged or removable cover as for bottle" , "Cap or top for container" , "Top or cover" , "Hat" .)