shutter – noun
1.
a solid or louvered movable cover for a window.
2.
a movable cover, slide, etc., for an opening.
3.
a person or thing that shuts.
4.
Photography . a mechanical device for opening and closing the aperture of a camera lens to expose film or the like.
–verb (used with object)
5.
to close or provide with shutters: She shuttered the windows.
6.
to close (a store or business operations) for the day or permanently.
–verb (used without object)
7.
to close or close down: The factory has shuttered temporarily.
Shudder:
–verb (used without object)
1.
to tremble with a sudden convulsive movement, as from horror, fear, or cold.
–noun
2.
a convulsive movement of the body, as from horror, fear, or cold.
She shuddered at the thought her husband might be able to see her through the partially closed shutters.
NOT: "She shuttered in fear."
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