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 an open letter last spring, faculty from the Gould School of Law said they were “unanimously opposed” to being included in it.

From Los Angeles Times ● Sep. 3, 2026

In an open letter, signed by more than 150 filmmakers, academics, writers and even a few rabbis, the group denounced “the outrageous smear campaign against our respected colleague Mark Ruffalo.”

From Los Angeles Times ● Sep. 1, 2026

Last week, more than 100 organizations around the world, including OpenAI and Anthropic, signed an open letter calling for a global effort to "strengthen cyber defenses" against AI-powered cybersecurity threats.

From Barron's ● Sep. 1, 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