Simple 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
Full Definition of pileup
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
Examples of pileup in a sentence
A five-car pileup slowed traffic.
<a pileup of e-mail messages that needed to be dealt with>
First Known Use of pileup
Learn More about pileup
Thesaurus: All synonyms and antonyms for pileup
Seen and Heard
What made you want to look up pileup? Please tell us where you read or heard it (including the quote, if possible).