shutter
1. shut.ter \'sh*t-*r\ n often attrib 1: one that shuts 2: a movable cover or screen for a window or door 3: a mechanical device of various forms attached to a camera to expose the film or plate by opening and closing an aperture 4: the movable louvers in a pipe organ by which the swell box is opened 2. shutter vt 1: to close with or by shutters 2: to furnish with shutters