do in

British  

verb

1. to murder or kill

2. to exhaust

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do in Idioms  

1. Tire out, exhaust, as in Running errands all day did me in . [ Colloquial ; early 1900s] Also see done in .

2. Kill, as in Mystery writers are always thinking of new ways to do their characters in . [ Slang ; early 1900s] Also see def. 4.

3. Ruin utterly; also cheat or swindle. For example, The five-alarm fire did in the whole block , or His so-called friend really did him in . [First half of 1900s]

4. do oneself in . Commit suicide, as in She was always threatening to do herself in . [ Slang ; first half of 1900s]

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Example Sentences

But Miller’s dramatic vision requires actors to relive the experiences of their characters, the way they do in De Santos’ production.

From Los Angeles Times • Apr. 1, 2026

The market potential for what AI can do in not just the digital economy but also the physical economy is massive.

From Barron's • Mar. 27, 2026

"Following the Kent outbreak, resources and information have been shared with higher education institutions and healthcare professionals to ensure they look for the signs of meningitis and know what to do in response," they added.

From BBC • Mar. 26, 2026

“The worst thing you can possibly do in a deal is seem desperate to make it,” the future president warned in The Art of the Deal.

From Slate • Mar. 26, 2026

“I had an uncle. A great-uncle. Saul. He lived down South, scraping by, like our people had to do in those days.”

From "Boy 2.0" by Tracey Baptiste