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 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 The shell of the castor bean is highly poisonous and can be used to make ricin. Eric Schmitt, New York Times, "ISIS May Be Waning, but Global Threats of Terrorism Continue to Spread," 6 July 2018 Tiny amounts of ricin can kill an adult if eaten, injected or inhaled. Frank Jordans, chicagotribune.com, "Tip from public helped Germany foil ricin attack plot," 20 June 2018 He is accused of having started procuring material, including a large quantity of seeds needed for the creation of ricin, online in mid-May. NBC News, "Ricin recovered from apartment in Cologne, Germany," 14 June 2018 Authorities found explosive powder and tutorials on how to make explosives and poison from materials such as ricin, the official said. Bloomberg.com, "French Government Says Attack Foiled, Egyptian Man Arrested," 18 May 2018 The court filing does not state what authorities believe Gibbs intended to do with the ricin. AJC.com, "Ricin suspect told cops he had ‘dangerous’ seeds. Then they let him go.," 26 Jan. 2018 Investigators found the ricin in a container that was double wrapped with plastic bags. Chris Harris, PEOPLE.com, "S.C. Woman Whose Boyfriend Died Under 'Suspicious' Circumstances Accused of Possessing Ricin," 2 May 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.

See More

First Known Use of ricin

1896, in the meaning defined above

History and Etymology for ricin

Latin ricinus castor-oil plant

Keep scrolling for more

Learn More about ricin

Statistics for ricin

Look-up Popularity

Time Traveler for ricin

The first known use of ricin was in 1896

See more words from the same year

Keep scrolling for more

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

What made you want to look up ricin? Please tell us where you read or heard it (including the quote, if possible).


a shady place in a garden or forest

Get Word of the Day daily email!

Test Your Vocabulary

Original Meanings Quiz

  • rembrandt-painting-a-young-scholar-and-his-tutor
  • Which of the following is the earliest known sense of the word awe?
Spell It

Can you spell these 10 commonly misspelled words?

Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!