mailernoun [ C ]
uk/ˈmeɪlər/usCOMMUNICATIONSUK 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