castor oil


Definition of castor oil

: a pale viscous fatty oil from castor beans used especially as a cathartic and as a lubricant and plasticizer

Examples of castor oil in a Sentence

Recent Examples on the Web The brand’s signature V decal is constructed from 100 percent castor oil, while the lining on the inside of the shoe is made from organic cotton and recycled plastic bottles. Wired, "Veja's New Running Shoe Subtracts the Plastic," 19 Sep. 2019 To advance labor, Jessa drank a castor oil smoothie (consult a doctor before doing this) and she was shown climbing up and down stairs to get her contractions to pick up. Amy Haneline, USA TODAY, "Jessa Duggar had an unexpected home birth on her couch," 21 June 2019 Shirley, via email Dear Heloise: For gas-free beans, soak 1 pound of beans overnight with 1 tablespoon of baking soda and 1 tablespoon of castor oil. Heloise, Washington Post, "Hints From Heloise: Keeping guacamole green?," 12 June 2019 But unlike rosemary oil and vitamin B5, both of which have studies that back up their aid in hair growth, scientific evidence surrounding castor oil is lacking. Kaleigh Fasanella, Allure, "Can Castor Oil Help Your Hair Grow? We Asked the Experts," 19 July 2018 While castor oil can become gummy in engines, the violet cress oil has less of a tendency to do this. John Wenz, Popular Mechanics, "This Purple Plant Has a Secret That Could Replace Synthetic Engine Oil," 27 Aug. 2018 This formula is enhanced with botanicals and castor oil. Tiffany Dodson, SELF, "7 Mistakes You’re Making When Doing a Twist Out," 13 Sep. 2018 There are microfibers in it that allegedly help build volume, while argan, jojoba, and coconut oil (note: not castor oil) help condition. Shannon Barbour, The Cut, "CoverGirl’s New Mascaras Condition and Thicken Lashes," 2 May 2018 The oil works similar to castor oil, but more efficiently at high temperatures. John Wenz, Popular Mechanics, "This Purple Plant Has a Secret That Could Replace Synthetic Engine Oil," 27 Aug. 2018

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

1746, in the meaning defined above

History and Etymology for castor oil

probably from its former use as a substitute for castoreum in medicine

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Time Traveler for castor oil

Time Traveler

The first known use of castor oil was in 1746

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Statistics for castor oil

Last Updated

21 Nov 2019

Cite this Entry

“Castor oil.” The Dictionary, Merriam-Webster Inc., Accessed 16 December 2019.

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More Definitions for castor oil

castor oil


English Language Learners Definition of castor oil

: a thick oil made from a tropical plant and used in the past as a medicine

castor oil

cas·​tor oil | \ ˈka-stər- \

Kids Definition of castor oil

: a thick yellowish liquid that comes from the seeds ( castor beans ) of a tropical herb and is used as a lubricant and as a strong laxative

castor oil


Medical Definition of castor oil

: a pale viscous fatty oil from castor beans used especially as a cathartic or lubricant

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More from Merriam-Webster on castor oil

Rhyming Dictionary: Words that rhyme with castor oil

Spanish Central: Translation of castor oil Encyclopedia article about castor oil

Comments on castor oil

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having a smooth flowing sound

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