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

This month, more than 5,000 Jewish public figures and allies — including several UC professors — signed an open letter opposing the accusation.

From Los Angeles Times ● Sep. 12, 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

Last week, 100 US tech companies signed a joint open letter warning governments and organisations worldwide about the growing cyber threat posed by AI, saying "the window is closing" to improve.

From BBC ● Sep. 2, 2026

In an open letter to township residents and policy makers, he criticized “idiosyncratic alternatives” to public districts, many of them “owned and operated by large national corporations whose number one mission is to enrich shareholders.”

From "Drama High" by Michael Sokolove