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:
“To have some account of my thoughts, manners, acquaintance and actions, when the hour arrives in which time is more nimble than memory, is the reason which induces me to keep a journal: a journal in which I must confess my every thought, must open my whole heart!”
—Frances Burney (1752–1840)
“This is the poem of the air,
Slowly in silent syllables recorded;
This is the secret of despair,
Long in its cloudy bosom hoarded,
Now whispered and revealed
To wood and field.”
—Henry Wadsworth Longfellow (1809–1882)