gallicacid

gal·lic acid (gălʹĭk, gôʹlĭk) n.

A colorless crystalline compound, C₇H₆O₅, derived from tannin and used as a tanning agent, as an ink dye, and in photography and the manufacture of paper.

  [French acide gallique, from galle, plant gall. See gall³.]

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