clancular
adj. secret, private

“Special Correspondence. I learn from a very high authority, whose name I am not at liberty to mention, (speaking to me at a place which I am not allowed to indicate and in a language which I am forbidden to use) — that Austria-Hungary is about to take a diplomatic step of the highest importance. What this step is, I am forbidden to say. But the consequences of it — which unfortunately I am pledged not to disclose — will be such as to effect results which I am not free to enumerate.” — Stephen Leacock, The Hohenzollerns in America, 1919