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)
“The secret of the illusoriness is in the necessity of a succession of moods or objects. Gladly we would anchor, but the anchorage is quicksand.”
—Ralph Waldo Emerson (1803–1882)