pileup

noun

pile·​up ˈpī(-ə)l-ˌəp 

1

: a collision involving usually several motor vehicles

2

a

: a jammed tangled mass or pile (as of motor vehicles or people) resulting from collision or accumulation

b

: accumulation

Synonyms of pileup

• accumulation
• collection
• pile
• jumble
• mixture
• gathering
• assemblage
• cumulation

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

For more than a decade, US immigration courts have faced an overwhelming pileup of cases, fueled largely by an increase in people crossing the US-Mexico border and seeking asylum. —Catherine E. Shoichet, CNN Money, 1 Dec. 2025

Less than 20 minutes after the first crash, on the other side of Glenwood Canyon, troopers responded to another pileup involving roughly 30 vehicles, according to the release. —Lauren Penington, Denver Post, 30 Nov. 2025

What To Know The pileup on I-70 was first reported just after noon on Saturday, near the 15-mile marker close to Terre Haute. —Hollie Silverman, MSNBC Newsweek, 29 Nov. 2025

But if the stadium doors open onto a wide field, people spread out, and there’s no pileup. —Avery Schuyler Nunn, Scientific American, 13 Nov. 2025

Word History

First Known Use

1900, in the meaning defined at sense 1

Rhymes for pileup

• buttercup
• backup
• blowup
• breakup
• buildup
• checkup
• cleanup
• holdup
• hookup
• lineup
• lockup
• makeup