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:
“But when with moving accents thou
Shalt constant faith and service vow,
Thy Celia shall receive those charms
With open ears, and with unfolded arms.”
—Thomas Carew (1589–1639)
“I make no secret of the fact that I would rather lie on a sofa than sweep beneath it. But you have to be efficient if you’re going to be lazy.”
—Shirley Conran (b. 1932)