Where does the expression “to keep under one’s hat” come from and What does it mean?

One would suppose that this warning would be as old as the first hat, but its actual history appears to have been no earlier than the closing years of the nineteenth century.

What is kept under the hat, of course, is retained within the head; that is, it remains a secret.

where does the expression to keep under ones hat come from and what does it mean
About Karen Hill

Karen Hill is a freelance writer, editor, and columnist for zippyfacts.com. Born in New York, she loves interesting random facts from all over the world.