tannic acid

noun Chemistry.

See under tannin.

Origin of tannic acid

First recorded in 1830–40

Definition for tannic acid (2 of 2)

[ tan-in ]
/ ˈtæn ɪn /


Chemistry. any of a group of astringent vegetable principles or compounds, chiefly complex glucosides of catechol and pyrogallol, as the reddish compound that gives the tanning properties to oak bark or the whitish compound that occurs in large quantities in nutgalls (common tannin, tannic acid).
any of these compounds occurring in wine and imparting an astringent taste, especially in red wine.

Origin of tannin

1795–1805; earlier tanin < F. See tan1, -in2


non·tan·nin, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for tannic acid

British Dictionary definitions for tannic acid

/ (ˈtænɪn) /


any of a class of yellowish or brownish solid compounds found in many plants and used as tanning agents, mordants, medical astringents, etc. Tannins are derivatives of gallic acid with the approximate formula C 76 H 52 O 46Also called: tannic acid

Word Origin for tannin

C19: from French tanin, from tan 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for tannic acid

tannic acid


A white or yellowish astringent powder used as a denaturant and in tanning and textiles.
A lustrous yellowish to light brown amorphous, powdered, flaked, or spongy mass derived from the bark and fruit of many plants and used as a mordant and to clarify wine and beer.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for tannic acid (1 of 2)

tannic acid
[ tănĭk ]

A lustrous, yellow-brown, amorphous substance, having the approximate chemical composition C76H52O46. It is derived from the bark and fruit of many plants and is used in tanning leather, in fixing dyes to materials, and in clarifying wine and beer.

Science definitions for tannic acid (2 of 2)

[ tănĭn ]

Any of various compounds, including tannic acid, that occur naturally in the bark and fruit of various plants, especially the nutgalls, certain oaks, and sumac. Tannins are polyphenols, and form yellowish to light brown amorphous masses that can be powdery, flaky, or spongy. They bind proteins and are used in dyeing, in tanning leather, in clarifying wine and beer, and as an astringent in medicine. Tannins also give color and flavor to black tea.
Any of various other substances that promote the tanning of leather, such as chromium salts.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.