sealed book

American  

noun

1. something beyond understanding and therefore unknown.

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sealed book British  

noun

1. another term for closed book

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Etymology

Origin of sealed book

First recorded in 1810–20

Example Sentences

Perhaps I cannot open my subject in any better way than by giving a few reasons why a knowledge of The Beyond has remained a sealed book for centuries.

From Beyond by Hubbard, Henry Seward

But he knew nothing of cricket and football; and the ordinary joys of the schoolboy's holidays—pantomimes, parties, and the like—were a sealed book to him.

From A Knight on Wheels by Hay, Ian

To his fellow-passengers Wagram was a sealed book, in that all conjectures as to his identity and his circumstance failed.

From The Red Derelict by Mitford, Bertram

The future is a sealed book to all of us.”

From Gwen Wynn A Romance of the Wye by Reid, Mayne

Rarely as we understand the sorrows of others, their joys are a sealed book indeed.

From The Village Notary by E?tv?s, J?zsef