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 is open to a war resister to judge between the combatants and wish success to the one who has justice on his side. By so judging he is more likely to bring peace between the two than by remaining a mere spectator.”
—Mohandas K. Gandhi (1869–1948)
“That is the whole secret of successful fighting. Get your enemy at a disadvantage; and never, on any account, fight him on equal terms.”
—George Bernard Shaw (1856–1950)