ri·​cin | \ ˈrī-sᵊn How to pronounce ricin (audio) , ˈri- \

Definition of ricin

: a poisonous protein in the castor bean

Examples of ricin in a Sentence

Recent Examples on the Web In his truck, officers found a plastic water gun and five tubes that tested positive for ricin. Amanda Rabines, Orlando Sentinel, 10 May 2022 At the hearing, Demissie said his client never made ricin, the Globe reported. Washington Post, 5 Apr. 2022 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 The seed for Saaem’s ricin idea didn’t involve him at all. Washington Post, 5 Apr. 2022 One example is ricin, which is produced naturally in castor seeds and is lethal to humans in the tiniest amounts. Amy Webb, The Atlantic, 14 Feb. 2022 It’s where Walt poisoned Lydia with ricin-laced Stevia. Dan Fellner, The Arizona Republic, 9 July 2021 Castor oil plant seeds contain ricin and are thus extremely poisonous. Leslie Nemo, Scientific American, 29 June 2021 Later in the day the FBI confirms that the letter tested positive for ricin. Cnn Editorial Research, CNN, 27 May 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ricin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ricin

1896, in the meaning defined above

History and Etymology for ricin

Latin ricinus castor-oil plant

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Dictionary Entries Near ricin



ricinelaidic acid

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Statistics for ricin

Last Updated

22 Jun 2022

Cite this Entry

“Ricin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ricin. Accessed 25 Jun. 2022.

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More Definitions for ricin


ri·​cin | \ ˈrīs-ᵊn, ˈris- How to pronounce ricin (audio) \

Medical Definition of ricin

: a poisonous protein in the castor bean

More from Merriam-Webster on ricin

Britannica.com: Encyclopedia article about ricin


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