pile·up or pile-up (pīlŭp′)
1. Informal A serious collision usually involving several motor vehicles.
2. An accumulation: "the pile-up of unsold autos" (New York Times).
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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