open letter

American  

noun

1. a letter, often of protest or criticism, addressed to a specific person, but intended to be brought to public attention.

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open letter British  

noun

1. a letter, esp one of protest, addressed to a person but also made public, as through the press

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Other Word Forms

• open-letter
  adjective

Etymology

Origin of open letter

First recorded in 1875–80

Example Sentences

See Examples For:

open letter

An Anthropic spokesman said people at all levels in the company are concerned about AI safety and that many employees had signed the pacing-the-frontier open letter in July.

From The Wall Street Journal ● Sep. 14, 2026

In 2020, she was among a cross-section of public figures who signed an open letter denouncing cancel culture, saying it weakens open debate by shutting people down.

From BBC ● Sep. 3, 2026

It also featured an open letter from 53 prominent women — including tennis great Billie Jean King, singer Judy Collins and Steinem — who revealed that they had undergone abortions.

From Los Angeles Times ● Sep. 3, 2026

OpenAI, Anthropic and more than 100 other organizations signed an open letter last week calling for a coordinated global response to AI-related cybersecurity risks, warning that the window to strengthen cyber defenses was limited.

From Barron's ● Sep. 3, 2026

I sent out members to mingle with crowds and try to discourage any further violence and sent an open letter to all the press denouncing them for "distorting" and inflating minor incidents.

From "Invisible Man" by Ralph Ellison