agnus castus

noun ag·nus cas·tus \ ¦ag-nəs-ˈka-stəs \

Definition of agnus castus

plural agnus castuses

1 : chaste tree 1

2 : an extract of the fruit of the chaste tree used in herbal medicine : chaste tree 2

In one trial, 48 women (aged between 23 and 29) diagnosed with infertility took agnus castus once daily for three months.
—Marilyn Glenville, Boost Your Fertility, 2009

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Origin and Etymology of agnus castus

Middle English, borrowed from Medieval Latin, literally “chaste agnus” (by association of the plant name with Greek hagnós “pure, chaste”), going back to Latin agnos, agnus, borrowed from Greek ágnos

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First Known Use: 14th century

in the meaning defined above

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