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Synonyms

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.

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
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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 .

Etymology

Origin of run-in

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Leyland's first try came as he scooped the ball over the line but his second came courtesy of an audacious run-in from halfway, which sent the home fans into raptures.

From BBC • Apr. 3, 2026

Meanwhile, it would seem like West Ham are the most likely to be relegated as not only do they currently sit in the bottom three, they also have the toughest run-in of the four sides.

From BBC • Mar. 12, 2026

With this police run-in, Country Joe and the Fish received a slew of press, riling up the public ahead of their Woodstock performance.

From Los Angeles Times • Mar. 8, 2026

Taran was less stoic, recounting a run-in with a neighbour who complained about the lights being out on the staircase.

From Barron's • Feb. 26, 2026

His mind was still on his run-in with Ike and Felix earlier in the day.

From "Shooting Kabul" by N. H. Senzai

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.