junk mail

American  

noun

1. unsolicited commercial mail or email.

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junk mail British  

noun

1. untargeted mail advertising goods or services

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junk mail Idioms  

1. Third-class mail, such as unsolicited advertisements and flyers, that is sent indiscriminately. For example, While we were on vacation the front hall filled up with junk mail. [c. 1950]

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Etymology

Origin of junk mail

First recorded in 1950–55

Example Sentences

My email inbox is starting to resemble the mailbox at my front door: stuffed full with junk mail and promos, with an important note tucked in here and there.

From The Wall Street Journal • Jan. 18, 2026

However, he said he did not remember seeing the email, and he thinks it must have gone into his junk mail.

From BBC • Jan. 18, 2026

Rice is also concerned that, like him, many people toss out the initial citation thinking it is junk mail.

From Los Angeles Times • May 17, 2024

Kingsley also suggests looking into cutting down on the junk mail she receives—you can read more about that from the Federal Trade Commission.

From Slate • Apr. 26, 2024

She is unable to stem the tide of junk mail that will continue to arrive for years, addressed to her dead husband.

From "The Namesake" by Jhumpa Lahiri