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

Boon had been on a long weekend hen do in Milan with five others before her airport ordeal.

From BBC • Apr. 13, 2026

To understand what the Iranians are likely to do with this newfound power, try to imagine what an amoral but rational actor would do in their shoes.

From MarketWatch • Apr. 11, 2026

Trump: “You know, if somebody said, ‘What would be your theory or what would you do in terms of Libya,’ I’d do one thing,” Trump said.

From Salon • Apr. 7, 2026

“We don’t want anyone to just toss it into the mailbox as we have been able to do in the past and have it counted,” she said.

From Los Angeles Times • Apr. 4, 2026

Arletta always said the true crafter made do in a pinch.

From "Hope Springs" by Jaime Berry