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

About 10 people suffered from non-life-threatening injuries as a result of the pileup, the county confirmed to USA TODAY. —Amaris Encinas, USA Today, 20 Jan. 2026

And finally… ▶️ Massive pileup in snowy Michigan A 100-plus vehicle pileup in Michigan on Monday brought traffic to a standstill during dangerous whiteout conditions. —Alexandra Banner, CNN Money, 20 Jan. 2026

In Michigan, whiteout conditions led to a 100-car pileup near Grand Rapids with a number of injuries after multiple tractor-trailers spun off the road. —Kathryn Prociv, NBC news, 20 Jan. 2026

The sheriff's office says the pileup involved about 100 vehicles, including dozens of semi-trucks. —David Chiu, PEOPLE, 19 Jan. 2026

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