Learner's definition of SOLE. always used before a noun. 1. : only or single. He became the sole heir to the property. the sole owner. The sole aim/objective/purpose of the program is to help the poor. She was the sole survivor of the tragedy. Icy roads were the sole cause of the accident. [+] more examples [-] hide examples [+] Example sentences [-] Hide examples
Dead letter mail or undeliverable mail is mail that cannot be delivered to the addressee or returned to the sender.ith increased collection and study of the postal markings originating from such offices, the body of literature on this obscure topic may grow. Many countries, including Canada and the United States, have issued special labels for envelopes that have travelled through the dead letter office.
First Class mail (has a real stamp on it) does get returned to the original sender, at no charge -- returning undeliverable mail is built into the 42 cost. Third class (bulk or 'junk') mail is normally NOT returned (even if you write return to sender on it) -- it is just discarded.Unless the sender has something printed on the envelope like Return Service Requested or Forwarding Service Requested or Address Service Requested.If those were printed on the original mail, then the Post Office will Return or Forward or whatever, and the original sender will pay for that service.hird class (bulk or 'junk') mail is normally NOT returned (even if you write return to sender on it) -- it is just discarded. Unless the sender has something printed on the envelope like Return Service Requested or Forwarding Service Requested or Address Service Requested.