polyphenol

noun

poly·​phe·​nol ˌpä-lē-ˈfē-ˌnōl 

-fi-ˈnōl

: a polyhydroxy phenol

especially : an antioxidant phytochemical

polyphenolic

ˌpä-lē-fi-ˈnō-lik  -ˈnä- 

adjective

Examples of polyphenol in a Sentence

Recent Examples on the Web

These herbs are similar nutritionally to other leafy vegetables, brimming with vitamins A, C and K, and plant compounds called polyphenols that have antioxidant and anti-inflammatory properties. —Ellie Krieger, Washington Post, 24 Mar. 2026

Stronger brews with higher polyphenol levels are likely to have a greater inhibitory effect than lighter roasts or weaker cups—good to know! —Lauren Manaker, SELF, 23 Mar. 2026

Ingredients like berries, walnuts, flax seeds, and leafy greens can provide polyphenols and antioxidants that help protect cells from oxidative stress. —Lynn Andriani, Martha Stewart, 12 Mar. 2026

Blueberries contain fiber and polyphenols that acts as fuel for beneficial gut bacteria. —Kathleen Ferraro, Verywell Health, 10 Mar. 2026

Word History

Etymology

International Scientific Vocabulary

First Known Use

1894, in the meaning defined above

Medical Definition

polyphenol

noun

poly·​phe·​nol ˌpäl-i-ˈfē-ˌnōl, -ˌnȯl, -fi-ˈ 

: a polyhydroxy phenol

especially : an antioxidant phytochemical (as chlorogenic acid) that tends to prevent or neutralize the damaging effects of free radicals

polyphenolic

-fi-ˈnō-lik  -ˈnäl-ik 

adjective