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

If this is food-history whiplash, bring on the 17-car pileup. — Scott Hocker, TheWeek, 9 July 2026

Novice runners can easily panic and make a wrong move that can cause a pileup or send someone into the path of a bull. — ABC News, 6 July 2026

On the second, Nigel Mansell’s slow start triggered a 12-car pileup. — Madeline Coleman, New York Times, 26 June 2026

Rideshare vehicles, commercial trucks, and multi-car pileups bring in extra insurance layers and additional parties that complicate everything. — Kaitlyn Gomez, Fort Worth Star-Telegram, 25 June 2026

Word History

First Known Use

1900, in the meaning defined at sense 1

Rhymes for pileup

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