shutter
n
1 a hinged doorlike cover, often louvred and usually one of a pair, for closing off a window
2 ♦
put up the shutters to close business at the end of the day or permanently
3 (Photog) an opaque shield in a camera that, when tripped, admits light to expose the film or plate for a predetermined period, usually a fraction of a second. It is either built into the lens system or lies in the focal plane of the lens (focal-plane shutter)
4 (Photog) a rotating device in a film projector that permits an image to be projected onto the screen only when the film is momentarily stationary
5 (Music) one of the louvred covers over the mouths of organ pipes, operated by the swell pedal
6 a person or thing that shuts
vb tr
7 to close with or as if with a shutter or shutters
8 to equip with a shutter or shutters