Deadlight n. : A strong shutter, made to fit open ports and keep out water in a storm.

Example:


Taxonomy
Operation Deadlight, U-boats, Germany, World War II, free encyclopedia, World War I, salvage, 02-12, Offensive, the Allies, 1945, Japan, uboat, Battle of the Atlantic, WWII, search, code name, defeat.

Defination from the web:
Deadlight was the code name for the scuttling of U-boats surrendered to the Allies after the defeat of Germany near the end of World War II. ... U-505 was slated for scuttling but Rear Admiral Daniel V. Gallery argued successfully that she did not fall under Operation Deadlight. ...