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 Customs and Border Protection officers in upstate New York arrested a woman attempting to enter the United States from Canada who is believed to have sent a letter containing the poison ricin to the White House last week. Anna Giaritelli, Washington Examiner, "Woman suspected of mailing ricin to Trump arrested trying to enter US from Canada," 21 Sep. 2020 According to the Centers for Disease Control and Prevention, if castor seeds are swallowed, ricin can be released and cause injury. CBS News, "Canadian authorities say letter containing ricin sent to White House," 19 Sep. 2020 Methods employed included rubbing toxins on victims’ skin and stabbing targets with an umbrella that dispensed a ricin-laced pellet, as Calder Walton noted for the Washington Post in 2018. Isis Davis-marks, Smithsonian Magazine, "You Could Own a Lipstick Gun, a Poison-Tipped Umbrella and Other KGB Spy Tools," 6 Nov. 2020 Shortly after Supreme Court Justice Ruth Bader Ginsburg’s death, the FBI and the U.S. Secret Service intercepted an envelope addressed to the White House containing the deadly substance ricin. Danielle Wallace, Fox News, "Trump campaign says Whitmer 'encouraging assassination attempts' against president with discreet TV message," 19 Oct. 2020 This is not the first time that U.S. officials have been targeted in ricin attacks. Katie Benner, New York Times, "Ricin Is Said to Have Been Sent to White House," 19 Sep. 2020 The sentence said ricin is part of the waste produced when castor oil is made. Adrian Vore, San Diego Union-Tribune, "The story behind newspaper corrections," 9 Oct. 2020 There have been several prior instances in which U.S. officials have been targeted with ricin sent through the mail. CBS News, "Suspect who allegedly sent envelope containing ricin to White House arrested," 21 Sep. 2020 There have been several prior instances in which U.S. officials have been targeted with ricin sent through the mail. Michael Balsamo, Anchorage Daily News, "Woman accused of sending poison letter to Trump arrested at Canadian border," 21 Sep. 2020

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.

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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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Statistics for ricin

Last Updated

22 Feb 2021

Cite this Entry

“Ricin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ricin. Accessed 3 Mar. 2021.

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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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