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

Nor is it a class action over $3 ATM fees that alerts consumers via junk mail.

From Slate • Jan. 13, 2026

Tags, receipts, ticket stubs, candy wrappers, even junk mail — they’re all gold for a junk journal.

From Los Angeles Times • Sep. 11, 2025

For instance, if I start receiving junk mail and spam from random companies and it’s addressed to “Rae Amazon Hodge,” I’ll know exactly what company sold me out.

From Salon • Mar. 22, 2024

My emails are mostly junk mail, but buried beneath that is one from Lucy’s address.

From "Dumplin'" by Julie Murphy