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ther·mo·a·cou·stic

(thûr′mō-ə-kstĭk)

adj.

Of or relating to a process using rapid, repetitive, high-amplitude acoustic waves to achieve separation of a pressurized gas mixture: a thermoacoustic condenser for use in refrigeration.

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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