thinking cap
nounUK /ˈθɪŋ.kɪŋ kæp/
US /ˈθɪŋ.kɪŋ kæp/
A pretend hat you put on when you need to think hard.
Put on your thinking cap and try to solve the puzzle.
OTHER MEANINGS
2. A humorous way to tell someone to start thinking seriously.
Time to put on your thinking cap and figure out the answer.
3. A mental state of being ready to concentrate and solve problems.
She had her thinking cap on during the whole math test.
4. A playful name for a hat worn during a quiz or brain game.
The kids made paper thinking caps before the spelling bee.