Definition of dead mail
: mail that is undeliverable because of faulty or illegible address and is unreturnable to the sender or that is unclaimed after a certain period of time and that must be sent to the dead-letter branch in the case of first-class mail or to the dead parcel-post branch for disposal
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Seen and Heard
What made you want to look up dead mail? Please tell us where you read or heard it (including the quote, if possible).