mailer computer application which sends e-mails I had a message saying the mailer was about to shut down and I didn't want to lose what I'd typed in .container for posting things You'll only hear from us if we want your program , or if you've enclosed return postage and a suitable mailer for returning disks we're unable to use . circular leaflet or e-mail message Hoping to entice music lovers to the April 19 concert , the council sent a colorful mailer to 25,000 homes emblazoned with the words , " the only time you want to see 100 gypsies on your doorstep".He also said the association planned a statewide mailer before the November election reminding voters of its endorsement . A frequent example involves hiding the true source of a negative campaign mailer . person or company who posts sth I'm not a casual mailer. I run a cottage industry of correspondence Ashcroft said that an FBI profile of the suspected mailer of the anthrax letters has also helped the investigation , although some scientists have complained that the profile was too vague to be useful .