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Related to dead letter: Dead letter mail
1. A letter that is unable to be delivered to the recipient or returned to the sender. The post office must destroy a dead letter if it can't be delivered or returned after a certain period of time.
2. An existing law or agreement that is no longer obeyed or enforced. The state's Sunday law is a dead letter as many stores open and conduct business on that day.
1. a piece of mail that is returned to the post office as both undeliverable and unreturnable. At the end of the year, the post office usually has bushels of dead letters. Some of the dead letters are opened to see if there is an address inside.
2. an issue, law, or matter that is no longer important or that no longer has force or power. His point about the need for education reform is a dead letter. It is being done now. This point of law is a dead letter since the last Supreme Court ruling on this matter.
1. An unclaimed or undelivered letter that is eventually destroyed or returned to the sender. For example, She moved without leaving a forwarding address, so her mail ended up in the dead letter office . [c. 1700]
2. A statute or directive that is still valid but in practice is not enforced. For example, The blue laws here are a dead letter; all the stores open on Sundays and holidays. [Second half of 1600s]
1. n. a letter that cannot move through the post office because the addressee does not exist or because the address is wrong or illegible. (Standard English.) Every now and then they open the dead letters to see if they can figure out who they were meant for.
2. n. an issue that does not matter anymore. This contract is a dead letter. Forget it!