rack one's brain

Idioms  

1. Also, cudgel one's brains. Strain to remember or find a solution, as in I've been racking my brain trying to recall where we put the key, or He's been cudgeling his brains all day over this problem. The first term, first recorded in 1583 as rack one's wit, alludes to the rack that is an instrument of torture, on which the victim's body was stretched until the joints were broken. The variant, from the same period, uses cudgel in the sense of “beat with a cudgel” (a short thick stick). Shakespeare used it in Hamlet (5:1): “Cudgel thy brains no more about it, for your dull ass will not bend his pace with beating.” Also see beat one's brains out.

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Example Sentences

"It's easy to bid one rack one's brain— I'm sure my poor head aches again, I've scratched it so and all in vain."

From Project Gutenberg

It's easy to bid one rack one's brain— I'm sure my poor head aches again,40 I've scratched it so, and all in vain.

From Project Gutenberg

It's easy to bid one rack one's brain— I'm sure my poor head aches again I've scratched it so, and all in vain.

From Project Gutenberg

It's easy to bid one rack one's brain—    40I'm sure my poor head aches again, I've scratched it so, and all in vain.

From Project Gutenberg

One does all one can to rack one's brain," she smiled, "and here you combine to do your utmost to confuse me!

From Project Gutenberg