pile·​up | \ ˈpī(-ə)l-ˌəp How to pronounce pileup (audio) \

Definition of pileup

1 : a collision involving usually several motor vehicles
2a : a jammed tangled mass or pile (as of motor vehicles or people) resulting from collision or accumulation

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Examples of pileup in a Sentence

A five-car pileup slowed traffic. a pileup of e-mail messages that needed to be dealt with

Recent Examples on the Web

Residents in Los Angeles have complained that Waze was redirecting traffic from the city's highways to residential areas en masse, sparking traffic pileups in neighborhoods. David Grossman, Popular Mechanics, "NYPD Wants Waze to Stop Warning People About DWI Traps," 7 Feb. 2019 This branch of highway runs parallel to the Lena River and can become impassably muddy from torrential downpours in the summer, causing pileups and roadblocks. Olivia Putnal, Woman's Day, "10 Awe-Inspiring Roads Around the World," 19 Oct. 2010 Sagan hit back by winning Stage 2 in an uphill sprint after Gaviria had fallen in a group pileup on the final corner. Joseph Wilson, The Seattle Times, "Gaviria beats Sagan again to claim 2nd Tour win on Stage 4," 10 July 2018 Pavel Sitnikov, the Russian who caused the pileup, was penalized for impeding. USA TODAY, "Viva Arianna: Italy's Fontana wins 500 meters in short track," 13 Feb. 2018 The big pileup, in the middle of the train, presented an unbelievable tableau. John Kelly, Washington Post, "All aboard as Answer Man revisits the day in 1976 a train derailed in Takoma," 6 Jan. 2018 Obviously, Facebook started the six-car pileup right now happening with another New York Times article, which also brought together stuff that had been there at the beginning and which people had talked about. Shirin Ghaffary, Recode, "After 20,000 workers walked out, Google said it got the message. The workers disagree.," 21 Nov. 2018 Waymo hasn't exactly avoided setbacks of its own, including a five-car pileup involving one of its cars just last month and a minor collision in May. But in all cases, officials concluded that humans, not the self-driving technology, were to blame. Sebastian Modak, Condé Nast Traveler, "Waymo Just Brought Us Even Closer to a Future with Self-Driving Cars," 25 July 2018 But Gaviria was involved in a group pileup inside the 3-kilometer zone that neutralizes the impact of accidents and could do nothing to stop Sagan from claiming a six-second overall lead and the yellow jersey. Joseph Wilson, BostonGlobe.com, "Peter Sagan sprints to the finish to win second stage of Tour de France," 8 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pileup.' 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 pileup

1900, in the meaning defined at sense 1

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Statistics for pileup

Last Updated

14 Apr 2019

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Time Traveler for pileup

The first known use of pileup was in 1900

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More Definitions for pileup



English Language Learners Definition of pileup

: an accident in which several or many vehicles crash into each other
: a large amount of something that has increased gradually over a period of time

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More from Merriam-Webster on pileup

Rhyming Dictionary: Words that rhyme with pileup

Thesaurus: All synonyms and antonyms for pileup

Spanish Central: Translation of pileup

Comments on pileup

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to speak slightingly about or to degrade

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