castor bean

noun

: the very poisonous seed of the castor-oil plant

Examples of castor bean in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Short pod mustard, castor bean, and tree tobacco are shooting up everywhere in the burn scar. Joy Benedict, CBS News, 4 June 2026 Portions of the trail were overgrown with castor bean and other invasives, but some park workers or kind volunteers are doing their best to keep it clear enough to pass. Jaclyn Cosgrove, Los Angeles Times, 30 Apr. 2026 Ricin is a highly toxic chemical that is naturally found in castor beans. Kirsty Hatcher, PEOPLE, 2 Apr. 2026 Letters and packages containing Ricin, a poison found in castor beans, have been sent to the president and other top U.S. officials in the past, including in 2018 and 2020. Kate Perez, USA Today, 22 Feb. 2026 See All Example Sentences for castor bean

Word History

First Known Use

1819, in the meaning defined above

Time Traveler
The first known use of castor bean was in 1819

Browse Nearby Words

Cite this Entry

“Castor bean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/castor%20bean. Accessed 16 Jun. 2026.

Kids Definition

castor bean

noun
cas·​tor bean
ˈkas-tər-
: the very poisonous seed of the castor-oil plant

Medical Definition

castor bean

noun
cas·​tor bean ˈkas-tər- How to pronounce castor bean (audio)
: the very poisonous seed of the castor-oil plant

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