Shown or hidden (8)
I believe the answer is:
screened
This clue is a double definition.
'shown' is the first definition.
(screening is a kind of showing)
'hidden' is the second definition.
'or' is the link.
(Other definitions for screened that I've seen before include "put on TV" , "Tested for disease or infection" , "Showed a movie" , "made available to view" , "shown on TV" .)