open secret

noun

1. something supposedly secret but actually known quite generally.

open secret

noun

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

Word History and Origins

Origin of open secret¹

First recorded in 1875–80

Idioms and Phrases

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.

Example Sentences

Students tell the BBC it was an open secret that Fesci ran both illicit sites but that everybody was too afraid to speak out.

From BBC

“It’s an open secret that Khaled Meshal has long been opposed to the idea Hamas throws all its eggs in the Iranian basket,” said analyst Lister.

From Los Angeles Times

The relationship between Nuzzi and Kennedy was an open secret in certain media spheres, according to Business Insider.

From Los Angeles Times

As the season came to a close, the fixing was an open secret in some dressing rooms.

From BBC

But after taking up the post “it became quite clear there was no plan” and quickly realised the Church of England was sitting on an open secret.

From BBC