tannin

/ˈtænɪn/
noun
  1. A natural substance found in plants, especially in bark, leaves, and unripe fruit, that gives a bitter taste and can bind to proteins, used in tanning leather and in some foods and drinks.
    • Tannins in red wine can make your mouth feel dry.
    • Unripe persimmons contain high levels of tannin, which makes them taste bitter.
    • The bark of the oak tree is rich in tannins used for leather production.
Synonyms
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