castor
1 Americannoun
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Also a brownish, unctuous substance with a strong, penetrating odor, secreted by certain glands in the groin of the beaver, used in medicine and perfumery.
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a hat made of beaver or rabbit fur.
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a heavy woolen cloth used mainly for coats.
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a beaver.
noun
noun
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the second brightest star, Alpha Geminorum, in the constellation Gemini: a multiple star consisting of six components lying close to the star Pollux. Distance: 52 light years
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classical myth See Castor and Pollux
noun
noun
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the brownish aromatic secretion of the anal glands of a beaver, used in perfumery and medicine
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the fur of the beaver
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a hat made of beaver or similar fur
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a less common name for beaver 1
Etymology
Origin of castor1
1350–1400; Middle English < Latin < Greek kástōr beaver
Origin of Castor1
Named after Castor; Castor and Pollux
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
“Measuring spoons, castor oil—blech!—a large cooking pot with a tight-fitting lid, moldy apples, goose fat, rinds of cheese...”
From Literature
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India mainly exports rice, shrimp, honey, vegetable extracts, castor oil and black pepper, while the US sends almonds, walnuts, pistachios, apples and lentils.
From BBC
The invasive species they brought — like black mustard, tree tobacco and castor bean — slowly crept into the ecosystem.
From Los Angeles Times
“Those, over there, are actually castor bean stalks,” Kleckner said as we zoomed past.
From Los Angeles Times
Ricin is a highly toxic poison naturally derived from castor oil plants.
From BBC
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.