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any of various complex phenolic substances of plant origin; used in tanning and in medicine

any of various complex phenolic substances of plant origin; used in tanning and in medicine

A lustrous powder, yellow to light-brown in color, that is found in tree bark (particularly oak), fruits, leaves, and tea. It is used medicinally as an astringent, commercially in tanning hides, and as a dye mordant. (Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984). It is also used as a histological fixative and stain.

See Tannin.

Astringent acid, C14H10O9, from tanbark and many plants; there are several varieties.

C14H10O9, powder, astringent, obtained from nut-galls and sumac leaves.