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n. Informal A serious collision usually involving several motor vehicles.

n. An accumulation: "the pile-up of unsold autos” ( New York Times).

n. Alternative spelling of pile-up.

n. multiple collisions of vehicles

"The pileup is a consequence of other states 'frustration with the influence of the geographically balanced foursome -- Iowa and New Hampshire, and, more recently, South Carolina and Nevada -- whose early-voting status is blessed by party rules."

collision   

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