deadlight
Noun
Meaning
A strong shutter, made to fit open ports and keep out water in a storm.
Source: Webster's dictionarySynonyms
Hypernyms
Phrases with the word
Examples
In the late 1990s, an approach was made to the British Ministry of Defence for salvage rights to the Operation Deadlight U-boats, by a firm which planned to raise up to a hundred of them.