A yellow flavonol, C15H10O7, found in glycoside form in tea and in many vegetables and fruits. It is an antioxidant and is used as a dietary supplement for its supposed antihistaminic, anti-inflammatory, and antitumor properties.
[Latin quercētum, oak forest (from quercus, oak; see perkwu- in the Appendix of Indo-European roots) + -IN.]
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