open secret

American  

noun

1. something supposedly secret but actually known quite generally.

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open secret British  

noun

1. something that is supposed to be secret but is widely known

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open secret Idioms  

1. Something that is supposedly clandestine but is in fact widely known, as in It's an open secret that both their children are adopted. This expression originated as the title of a Spanish play by Calderón, El Secreto a Voces (“The Noisy Secret”), which was translated by Carlo Gozzi into Italian as Il pubblico secreto (1769). In English the term came into general use during the 1800s.

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Etymology

Origin of open secret

First recorded in 1875–80

Example Sentences

On Tuesday, the defense insisted on the Brazao brothers' innocence, while noting that links between local power and criminals were an open secret.

From Barron's • Feb. 25, 2026

Soon it was an open secret among traders that Americans were using Polymarket despite the ban.

From The Wall Street Journal • Feb. 2, 2026

It’s an open secret among general audiences and industry figures alike.

From Salon • Jan. 25, 2026

The scale of essay cheating was an "open secret" and one of the reasons he left the sector in 2024, Mr Foster said.

From BBC • Dec. 16, 2025

The open secret of the Maafa had been bothering me throughout my time here, and it had taken something High John said to make me understand.

From "Tristan Strong Punches a Hole in the Sky" by Kwame Mbalia