mailer

/ˈmeɪlər/ noun [C] COMMUNICATIONS

Definition

› (UK mailshot) a paper advertisement sent to homes or businesses: An election mailer reached three million homes. The direct mailer we produced was sent out to 250 members. → See also mailing

› a company, person, or software program that sends lots of letters or messages, especially many copies of the same thing: bulk/junk/mass mailer The junk mailer was fined for sending billions of messages without permission from the recipients.

› US a special envelope or container for sending things that can easily break, have an unusual shape, or are very small: Robert copied the files onto a disk, put a label on it, and put it in a mailer. → Compare postal packet

(Definition of mailer noun from the Cambridge Business English Dictionary © Cambridge University Press)