Opaque

From Elendor

 Flag:  OPAQUE  (all types)

 When set on yourself, it prevents other players from 
 seeing what you are carrying in your inventory. This applies to
 everyone and everything, even wizards and royalty, or to stuff
 that you own. It works the same way on objects.

 When set on an exit in a TRANSPARENT room, the exit is displayed
 as if the room weren't TRANSPARENT.

 Meaningless for rooms.

 See also: transparent, look