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ar·sen·ic acid

(är-sĕnĭk)

A poisonous, hygroscopic, white, translucent crystalline compound, H₃AsO₄, occurring chiefly in its hemihydrate form, used to manufacture arsenates and glass, and in treating wood.

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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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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