agnus castus


ag·​nus cas·​tus
plural agnus castuses
: 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


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

Time Traveler
The first known use of agnus castus was in the 14th century

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Dictionary Entries Near agnus castus

Cite this Entry

“Agnus castus.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2024.

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