dead letter

  1. a law, ordinance, etc., that has lost its force but has not been formally repealed or abolished.
  2. a letter that cannot reach the addressee or be returned to the sender, usually because of incorrect address, and that is sent to and handled in a special division or department (dead-letter office) of a general post office.

Origin of dead letter

First recorded in 1570–80
Related formsdead-let·ter, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for dead letter

Historical Examples of dead letter

  • After a long time it came back from the German dead-letter office.


    Edward Bellamy

  • System, punctuality, industry, belong to the Dead-letter Office.

  • If people do not steal our horses the reward is a dead-letter.


    Rolf Boldrewood

  • I got it back in the face by way of the dead-letter office where they know me.


    Edgar Wilson (Bill) Nye

  • But the most exciting day of all was when they visited the Dead-letter Office.

British Dictionary definitions for dead letter

dead letter

  1. a letter that cannot be delivered or returned because it lacks adequate directions
  2. a law or ordinance that is no longer enforced but has not been formally repealed
  3. informal anything considered no longer worthy of consideration
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Idioms and Phrases with dead letter

dead letter


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]


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]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.