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

Perhaps the biggest challenge ahead for Apple is to build a category-defining product that it hasn’t been able to do in years.

From Los Angeles Times • Apr. 22, 2026

“That’s usually like 90% of the work that you do in a kitchen.”

From Salon • Apr. 19, 2026

She shouldn’t feel like a failure for doing what she needs to do in order to feed her kid.

From Slate • Apr. 19, 2026

Several U.S. states do, in fact, have key exceptions that may allow certain creditors to reach trust assets.

From MarketWatch • Apr. 16, 2026

Spying via telephone was such a modern concept I could barely even imagine such a thing, nor could I begin to think of what I could do in order to investigate.

From "The Brightwood Code" by Monica Hesse