An open secret is a concept or idea that is "officially" secret or restricted in knowledge, but is actually widely known; or refers to something which is widely known to be true, but which none of the people most intimately concerned are willing to categorically acknowledge in public.
Famous quotes containing the words open and/or secret:
“It doesn’t do good to open doors for someone who doesn’t have the price to get in. If he has the price, he may not need the laws. There is no law saying the Negro has to live in Harlem or Watts.”
—Ronald Reagan (b. 1911)
“Mad? Is one who has solved the secret of life to be considered mad?”
—Edward T. Lowe. Frank Strayer. Dr. von Niemann (Lionel Atwill)