What does tannin mean?
Tannin refers to a chemically diverse group of polyphenolic substances produced by plants. Although individual tannins differ in structure, many bind with proteins and other molecules, producing the dry, puckering sensation known as astringency. They are especially noticeable in strong tea, red wine, unripe fruit, and some vegetables, and they also occur in bark and other plant tissues used for tanning leather. The word is commonly used in discussions of wine, brewing, food science, nutrition, leather production, and plant chemistry. When discussing a specific sample, writers may speak of its tannin content or tannin levels; when discussing the class as a whole, the plural “tannins” is natural. Although “tannic acid” is often used as a loose synonym, tannin is the broader term. Understanding tannins helps explain both the desirable structure of a well-made beverage and the sometimes unpleasant drying sensation associated with overbrewed tea or overly tannic wine.
nounA group of polyphenolic plant compounds that give tea, wine, and some fruits and vegetables an astringent, often drying or puckering quality. Tannins are also used in the tanning of leather and in the manufacture of certain industrial products.
- A polyphenolic compound or group of compounds found especially in plant tissues, including tea leaves, grape skins, and tree bark, and characterized by an astringent taste or effect.
- A tanning material used to treat hides and convert them into leather.
"The green tea had a pronounced bitterness and a tannic astringency that lingered on the palate."
"The tannin in the leaves gave the infusion its characteristic astringency."
"Vegetable tannins are being studied for their ability to interact with proteins and other compounds."
The plural is standard when referring to several individual compounds, the class of plant polyphenols collectively, or the amount of tannin in a substance.
"Different tannins affect the texture and bitterness of a wine in different ways."
Tannins are the reason strong tea can make your mouth feel dramatically tighter, and the same plant compounds are at work in the astringency of red wine.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does tannin come from?
English borrowed the word from French tanin, an older form of tanin, a substance used in tanning. The French word developed from tan, referring to bark or other material used to tan hides. Related English forms such as tanner and tannery belong to the same tanning tradition, while tannic was formed later as a derivative of the English word.
Related word forms
How tannin is actually used
Usually a technical or food-and-wine term; it is often used in the plural when referring to the class of compounds or to their measurable amount. In general writing, the word tends to suggest both plant origin and a distinctive astringent quality.
Easily confused with tannin
Tannin names a broader group of plant polyphenols, whereas tannic acid is a particular substance within that group and is sometimes used loosely as a synonym.