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 (rī′sĭn, rĭs′ĭn)
A poisonous protein extracted from the castor bean and used as a biochemical reagent.

[German Ricin, from New Latin Ricinus, castor-oil plant genus, from Latin ricinus, sheep tick, castor-oil plant (the plant being so called from the ticklike appearance of castor beans ), of unknown origin.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈraɪsɪn; ˈrɪs-)
(Biochemistry) biochem a highly toxic protein, a lectin, derived from castor-oil seeds: used in experimental cancer therapy
[C19: from New Latin Ricinus genus name, from Latin: castor-oil plant]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈraɪ sɪn, ˈrɪs ɪn)

a white, poisonous, protein powder from the bean of the castor-oil plant.
[1895–1900; < New Latin Ricinus genus name, Latin: castor-oil plant, literally, tick (parasite)]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ricin - a toxic protein extracted from castor beans; used as a chemical reagent; can be used as a bioweapon; "one milligram of ricin can kill an adult"
albumen, albumin - a simple water-soluble protein found in many animal tissues and liquids
toxin - a poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


n ricina
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in periodicals archive ?
Small doses of ricin are lethal to humans if ingested, inhaled, or injected and there are no known antidotes, according to a statement from the Treasury Department.
The envelope, which was received by Collins' husband, Thomas Daffron, comprised a letter bearing the note saying the package contained the toxic substance Ricin. Collins was on her way home from Washington at the time, (https://thehill.com/homenews/senate/411496-suspicious-letter-mailed-to-maine-home-of-susan-collins) the Hill &nbsp;reported.&nbsp;
Two or more packages delivered to the Pentagon this week were suspected to contain the deadly poison ricin, an official said Tuesday.
[U.S.A.], Oct 03 (ANI): At least two packages suspected of containing deadly poison Ricin, were found by the authorities at a Pentagon mail screening facility on Monday.
M2 PHARMA-September 5, 2018-Soligenix Publishes Positive Long-Term Data Supporting Thermostability and Conformational Integrity of the RiVax Ricin Toxin Vaccine
A Tunisian detained in Germany on suspicion of planning an Islamist-motivated attack produced ricin and tested the lethal toxin on a hamster, prosecutors said on Friday.
had ordered suspicious material and believed he was working to build an explosive device containing the deadly substance ricin. German intelligence had learned that Sief Allah H.
Soligenix announced that it has received notice of allowance for European and Canadian patent applications further extending protection around ThermoVax including coverage of the company's ricin toxin vaccine, RiVax.
NNA - France's interior minister says authorities have thwarted a possible attack using ricin or explosives and arrested two brothers.
M2 EQUITYBITES-March 27, 2018-European Commission grants orphan drug designation to Soligenix's recombinant modified ricin toxin A-chain subunit
The police also said--and Rezaei's lawyer confirmed to Fox News--that Rezaei was hospitalized in 2013 for ricin poisoning.
A DAD-OF-TWO, caged for plotting to buy enough ricin to kill 1,400 people, has failed to convince top judges his trial was unfair.