Definitions
a container for something to be mailed
Word origin
From mail + -er.
Used in a sentence
“Large and frequent mailers may send material on a monthly basis to their house lists, test acquisitions several times a year to drum up new donors, and perhaps do a few special appeals on top of that.”
“The cassette came in a brown paper mailer.”
“Do they recall your latest mailer? Did you ever sell an armoire through ads on hard-rock radio? Find out with low-cost "intercept" surveys of customers as they leave the store.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Postal packet”6 letters
02“Postal envelope”6 letters
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