agnus castus

noun

ag·​nus cas·​tus

¦ag-nəs-ˈka-stəs

plural agnus castuses

1

: chaste tree sense 1

2

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

Word History

Etymology

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

First Known Use

14th century, in the meaning defined above

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