noun (1)
cas·​tor | \ ˈka-stər How to pronounce castor (audio) \

Definition of castor

 (Entry 1 of 2)

3 : a beaver hat


noun (2)
Cas·​tor | \ ˈka-stər How to pronounce Castor (audio) \

Definition of Castor (Entry 2 of 2)

1 : one of the Dioscuri
2 : the more northern of the two bright stars in Gemini

Examples of castor in a Sentence

Recent Examples on the Web: Noun Every few days, Brown saturates her hair with a leave-in conditioner and an oil of choice (jojoba, vitamin E, or castor), then part it into two ponytails. Akili King, Vogue, "Kellie Brown on Self-Love, Inspiring Community, and Sticking to a Beauty Routine," 30 July 2020 The wax — which is made of beeswax, castor seed oil, and lanolin — goes on thick but immediately melts upon contact with skin. Audrey Noble, Allure, "Ina Garten Shares Her Favorite Glossier Product (and It’s Probably Your Favorite, Too)," 23 Jan. 2020 The oil is made from castor seeds harvested by about 300 farmers in Haiti. Gary Levin, USA TODAY, "'Shark Tank' recap: Haitian beauty-product sellers get tough love from Mr. Wonderful," 14 Jan. 2020 The dark Ollivanders-esque room is a dream for Harry Potter fans, especially since real-life potion ingredients like dragon’s blood, mandrake root, and castor are found in the many dusty drawers. al, "Plan the ultimate holiday getaway to this historic Virginia town," 9 Dec. 2019 The show also expands the familiar story to include a castor-oil-dispensing nanny nemesis for our bumbershoot-sailing Miss Poppins. Web Behrens,, "40 things to do in the Chicago area with the kids in December," 24 Nov. 2019 Called Råvaror, the new collection includes 20 new products: a daybed, a sofa, tables, a mini kitchen, storage solutions on castors, textiles, and lighting. Elizabeth Gulino, House Beautiful, "Ikea’s New Packable Furniture Will Change Your Life," 24 July 2019 Olérys and Laugier manufactory sugar castor from Moustiers (c. 1750) Photo: Sidney R. Knafel Collection French faience has its roots in Italy, its name derived from the northern Italian city Faenza, an important producer of majolica. Barrymore Laurence Scherer, WSJ, "‘Masterpieces of French Faience: Selections From the Sidney R. Knafel Collection’ Review: Not Dishwasher Safe," 1 Jan. 2019 Star players include collagen-boosting raspberry seed oil, moisturizing castor seed oil, and antioxidant-heavy camellia japonica seed oil. Sophie Wirt, Allure, "Exclusive: Wander Beauty Launches Glow Ahead, Its First-Ever Facial Oil," 17 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'castor.' 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 castor

Noun (1)

14th century, in the meaning defined at sense 1

Noun (2)

15th century, in the meaning defined at sense 1

History and Etymology for castor

Noun (1)

Middle English, from Latin, from Greek kastōr, from Kastōr Castor

Noun (2)

Latin, from Greek Kastōr

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Time Traveler for castor

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The first known use of castor was in the 14th century

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Statistics for castor

Last Updated

2 Aug 2020

Cite this Entry

“Castor.” Dictionary, Merriam-Webster, Accessed 12 Aug. 2020.

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Thesaurus: All synonyms and antonyms for castor

Rhyming Dictionary: Words that rhyme with castor

Spanish Central: Translation of castor Encyclopedia article about castor

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