run-in

American  

[ruhn-in] / ˈrʌnˌɪn /

noun

1. a quarrel; argument.

2. Printing. matter that is added to a text, especially without indenting for a new paragraph.

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adjective

1. Printing. added to a text without indenting.

run in British  

verb

1. to run (an engine) gently, usually for a specified period when it is new, in order that the running surfaces may become polished

2. (tr) to insert or include

3. (intr) (of an aircraft) to approach a point or target

4. informal (tr) to take into custody; arrest

   he was run in for assault

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noun

1. informal an argument or quarrel

   he had a run-in with the boss yesterday

2. an approach to the end of an event, etc

   the run-in to the championship

3. printing matter inserted in an existing paragraph

run in Idioms  

1. Insert or include something extra, as in Can you run this map in with the text? [Early 1800s]

2. Also, run on . In printing, make a solid body of text without a paragraph or other break, as in The quotation should be run in rather than set as a paragraph .

3. Also, run someone in . Take someone into custody, as in The police were going to run him in, but he got away . [ Slang ; mid-1800s]

4. Visit someone briefly, as in If I have time, I'll run in to see Aunt Mary . [Second half of 1800s]

5. Break something or someone in, as in Let's run in the new model on a short flight . [Early 1900s] Also see run into .

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Etymology

Origin of run-in

First recorded in 1900–05; noun, adj. use of verb phrase run in

Explanation

A run-in is a confrontation or an argument. Peaceful protests go more smoothly when protestors avoid run-ins with the police. If you get in a fight with your brother about how he never loads the dishwasher, you can call that a run-in. A more serious kind of run-in might be a shoplifter's run-in with a store security guard or a basketball player's angry run-in with a referee that gets him benched for the rest of the season. Before 1905, run-in meant an instance of actually running somewhere.

Example Sentences

The big concern for director of rugby Lam will be losing a number of players to injury ahead of the run-in, including games against the top two in Northampton Saints and Bath.

From BBC • Apr. 24, 2026

Although Manchester City have a tougher run-in than Arsenal on paper, their knowhow in terms of getting the job done during a tight race will prove crucial.

From BBC • Apr. 24, 2026

So do Arsenal need to change their mindset in the run-in for the title?

From BBC • Apr. 23, 2026

With five games remaining Spurs will definitely think their run-in, at least on paper, gives them every chance of staying up.

From BBC • Apr. 22, 2026

A run-in with Albert convinced Mr. Whiskers that he’d best forget about any chicken dinners.

From "Hattie Big Sky" by Kirby Larson

Related Words

• altercation
• confrontation
• falling-out
• quarrel
• skirmish
• tussle