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ac·cel·er·a·tor

(ăk-sĕlə-rā′tər)

1. A device, especially the gas pedal of a motor vehicle, for increasing speed.

2. Chemistry A substance that increases the speed of a reaction.

3. Physics A particle accelerator.

4. Business An organization that provides new businesses with mentoring, funding, and other services and resources, usually for a limited period of a few months, in exchange for equity.

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:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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