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

The star ingredients here are oil-absorbing clays (including kaolin and bentonite) and the brand’s signature grapeseed polyphenols, which provide free radical protection as well as combat sebum oxidation—the reason blackheads appear dark. —Emily Orofino, Vogue, 21 Nov. 2025

Yes, the fuzzy part, because that’s where much of the fiber and polyphenols are found. —Dr. Steven Gundry, CNBC, 21 Nov. 2025

The polyphenols in red grapes, specifically quercetin, myricetin, and resveratrol, may intervene with these diabetic complications. —Kathi Valeii Published, Verywell Health, 13 Nov. 2025

Shai said green tea's EGCG antioxidant compounds, along with the healthy fats and polyphenols in walnuts, likely drove the change, with Mankai adding support through gut–brain and metabolic pathways. —Deirdre Bardolf, FOXNews.com, 12 Nov. 2025

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