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tannic acid

1. A hydrolyzable tannin in the form of a lustrous yellowish to light brown amorphous, powdered, flaked, or spongy substance having the approximate composition C₇₆H₅₂O₄₆, derived from certain plants and used in tanning leather, in fixing dyes to materials, and in clarifying wine and beer.

2. See tannin.

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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