ricin

noun

ri·​cin ˈrī-sᵊn How to pronounce ricin (audio)
ˈri-
: a poisonous protein in the castor bean

Examples of ricin 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.
In his truck, officers found a plastic water gun and five tubes that tested positive for ricin. — Amanda Rabines, Orlando Sentinel, 10 May 2022 Per Corriere della Sera, traces of ricin were found in the blood of the two women as well as in Di Ielsi's hair. — Kirsty Hatcher, PEOPLE, 2 Apr. 2026 In 2018, a letter that claimed to contain ricin led to a full biohazard response by first responders at her home. — Fox News, 11 May 2022 Toxicology testing was carried out on the two victims, with blood samples showing traces of the potent poison ricin, according to lawyers for the doctors. — Barbie Latza Nadeau, CNN Money, 3 Apr. 2026 See All Example Sentences for ricin

Word History

Etymology

Latin ricinus castor-oil plant

First Known Use

1896, in the meaning defined above

Time Traveler
The first known use of ricin was in 1896

Rhymes for ricin

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Browse Nearby Words

Ricimer
ricin
ricinelaidic acid
See all Nearby Words

Cite this Entry

“Ricin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ricin. Accessed 7 Jul. 2026.

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Medical Definition

ricin

noun
ri·​cin ˈrīs-ᵊn, ˈris- How to pronounce ricin (audio)
: a poisonous protein in the castor bean

More from Merriam-Webster on ricin

Britannica.com: Encyclopedia article about ricin

Last Updated: - Updated example sentences
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