\ˈrən-ˌin \

Definition of run-in 

(Entry 1 of 2)

1 British : the final part of a race or racetrack

3 : something inserted as a substantial addition in copy or typeset matter

run in


Definition of run in (Entry 2 of 2)

transitive verb

1a : to insert as additional matter

b : to make (typeset matter) continuous without a paragraph or other break

2 : to arrest for a usually minor offense

3 chiefly British : to break in (a new machine) gradually by careful operation

intransitive verb

: to pay a casual visit

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Examples of run-in in a Sentence


I just thought I'd run in and pick up my package. if we catch you shoplifting again, we're going to run you in

Recent Examples on the Web: Verb

This article originally ran in the November/December 2018 issue of Redbook. Lindsey Benoit O'connell, Redbook, "Connie Britton Shares Her Rules for a Totally Chill Holiday Season," 29 Oct. 2018 But all too often firefighters run in without a hose, or carry one that’s too short or doesn’t have a water supply, reports show. Mike Hendricks, kansascity, "In a tragic loop, firefighters continue to die from preventable mistakes," 13 July 2018 In some cases, susceptibility to a specific kind of infection—Candida, for example—runs in families. Claudia Wallis, Scientific American, "Extreme Flu? Weird Encephalitis? It May Be Your Genes," 13 July 2018 Over their 40 years of friendship and on-and-off musical collaboration, their careers have run in tandem, with both having assembled staggeringly broad catalogs of work, defying genre classification and commercial convention. Joshua Zucker,, "John Zorn and Bill Laswell make rare duo appearance at the Chapel," 11 July 2018 That race could have run in the tens of millions of dollars, though labor leaders say the negotiation was more about avoiding an existential threat to municipal budgets than saving money on a campaign. Alexei Koseff, sacbee, "After 'wake-up call' from Supreme Court, California unions face tough political choices," 3 July 2018 The suit, which was later dismissed, centered around an article the Capital Gazette had run in 2011 that covered a criminal harassment case against Ramos, who had reportedly harassed a former classmate of his. Natasha Bach, Fortune, "What You Need to Know About the 'Capital Gazette' Mass Shooting," 29 June 2018 Zach Stewart earned the win, giving up nine hits and three runs in six innings, striking out 5. Hartford Courant,, "Jamar Walton Leads Bees Past Road Warriors," 24 June 2018 The Marlins two more runs in the ninth off Sam Dyson. Clark Spencer, miamiherald, "Marlins and Giants play nice. But it's Giants who come out smiling.," 20 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'run-in.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of run-in


1799, in the meaning defined at sense 1


1888, in the meaning defined at sense 1b

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Statistics for run-in

Look-up Popularity

Time Traveler for run-in

The first known use of run-in was in 1799

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More Definitions for run-in



English Language Learners Definition of run-in

: an angry argument



Kids Definition of run-in

: an angry argument

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More from Merriam-Webster on run-in

Rhyming Dictionary: Words that rhyme with run-in

Thesaurus: All synonyms and antonyms for run-in

Spanish Central: Translation of run-in

Nglish: Translation of run-in for Spanish Speakers

Comments on run-in

What made you want to look up run-in? Please tell us where you read or heard it (including the quote, if possible).


to make faulty or ineffective

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