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
PILEUP Defined for English Language Learners
Definition of pileup for English Language Learners
: 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
Learn More about pileup
Thesaurus: All synonyms and antonyms for pileup
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