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

According to the Centers for Disease Control and Prevention, if it is made into a partially purified material or refined, ricin can be used as a weapon capable of causing death under certain circumstances. Robert Burns, The Seattle Times, "Packages with suspected ricin sent to Pentagon, Navy chiefs," 2 Oct. 2018 As Markov walked across London’s Waterloo Bridge, an assailant stabbed him with the lethal umbrella, implanting a pellet laced with ricin. Calder Walton, Washington Post, "Russia has a long history of eliminating ‘enemies of the state’," 13 Mar. 2018 In 1978, the prizewinning Bulgarian writer Georgi Markov, then working for the BBC in London, was killed by an umbrella tip that shot a pellet containing the poison ricin into his leg. Amanda Foreman, WSJ, "Poison and Politics," 6 Sep. 2018 Tunisian suspected of plotting ricin attack in Germany: German authorities have thwarted a plot by a Tunisian man who created the deadly toxin ricin and planned to use it in an Islamist extremist attack in Germany, prosecutors said. Washington Post, "World Digest: June 14, 2018," 14 June 2018 Critics are still incensed over Collins’ vote for U.S. Supreme Court nominee Brett Kavanaugh , for which protesters rallied at her office and a letter that mentioned ricin was sent to her home. David Sharp, The Seattle Times, "What is Dems’ quest to unseat Collins missing? A candidate," 28 Jan. 2019 According to the Centers for Disease Control and Prevention, ricin is found naturally in castor beans, and can be extracted to make a powder, mist or pellet containing the concentrated poison. Nancy A. Youssef, WSJ, "Letters to Pentagon Held Castor Seeds, Not Ricin; Utah Man Is Held," 3 Oct. 2018 According to the Centers for Disease Control and Prevention, if inhaled or ingested, ricin can cause vomiting, diarrhea and respiratory problems. Nancy A. Youssef, WSJ, "Two Letters Sent to the Pentagon Test Positive for Ricin," 2 Oct. 2018 The seeds of the castor bean plant are naturally poisonous and can be used to create ricin. Kirsten Grieshaber And David Rising, chicagotribune.com, "German authorities thwart plot to use deadly toxin in attack, prosecutors say," 14 June 2018

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

8 Sep 2019

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Time Traveler for ricin

The first known use of ricin was in 1896

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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

Comments on ricin

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to make a temporary encampment

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