What is Shutter?

Shutter definition and meaning on Dictionary terms:
a solid or louvered movable cover for a window.
a movable cover, slide, etc., for an opening.
a person or thing that shuts.

Photography. a mechanical device for opening and closing the aperture of a camera lens to expose film or the like.

verb (used with object)
to close or provide with shutters: She shuttered the windows.
to close (a store or business operations) for the day or permanently.

verb (used without object)
to close or close down: The factory has shuttered temporarily.