To tremble or to shiver in a convulsive manner: "It was so cold that she started to shudder and could not stop until she went inside to get warm."

The act of trembling or shivering in an uncontrollable manner: "The man felt a shudder go up his spine when he thought of what could have happened if he had missed his plane."

1. A moveable cover that can be closed over the outside of a window or a door: "He decided to paint the shutter on the porch a bright green."
2. Part of a camera that opens and shuts to allow light to expose the film: "The shutter on her camera got stuck and so she had to get it repaired."

To move the hinged parallel slats of a cover in a door or over windows to admit air and light or for keeping rain from pouring against the windows: "He wanted to shutter the windows before the rain started."

"She wanted to shutter the windows to keep the house cooler by diminishing the glare of the sun during the summer heat."