thinking cap

noun

1. a state of mind marked by reflection or concentration:

   If we put on our thinking caps, we may come up with the answer.

Word History and Origins

Origin of thinking cap¹

First recorded in 1870–75

Idioms and Phrases

see put on one's thinking cap .

Example Sentences

But his head was too hot to wear a thinking cap, and no story would come at his half-hearted call.

From Project Gutenberg

Now you put your thinking cap on and invent a name, something romantic and pretty.

From Project Gutenberg

Old Styf answered "yes" at once to their request, and put on his red thinking cap.

From Project Gutenberg

There was nothing for it but to bow to the inevitable, break my journey, and put my thinking-cap on.

From Project Gutenberg

"And this head of mine would have to put on its thinking-cap," he pursued jovially.

From Project Gutenberg