ˌdead ˈletter BrE AmE noun [countable]
1 . a law, idea etc that still exists but that people no longer obey
2 . a letter that cannot be delivered or returned
ˌdead ˈletter BrE AmE noun [countable]
1 . a law, idea etc that still exists but that people no longer obey
2 . a letter that cannot be delivered or returned
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012