deadlight

Noun

 * 1)  A strong (often wooden) shutter fitted over a porthole, that can be closed in bad weather to keep water out and discourage the glass windows from breaking.
 * 2)  A deck prism, a device to allow light into the cabin of boat through the deck.
 * 3)  An eye.
 * 4)  An eyelid.
 * 1)  An eyelid.