• synonyms

castor oil

  1. a colorless to pale yellow, viscid liquid, usually obtained from the castor bean by a pressing process: used as a lubricant, in the manufacture of certain soaps and creams, and in medicine chiefly as a cathartic.
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Origin of castor oil

1740–50; castor (perhaps variant spelling of caster) + oil; perhaps so called because of its purgative effect
Also called ricinus oil.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for castor oil

Historical Examples of castor oil

  • She gave it castor-oil, and it recovered, but has never sung since that time.

    Harper's Young People, July 6, 1880


  • Kiki (the castor-oil bean) is a kind of fruit sowed in furrows.

  • They took ipecacuanha, castor-oil, or sulphate of soda, as if they enjoyed them.

  • When I come back you must reward it with an anointing of tallow or castor-oil.

  • In these larger European motors, castor-oil is used largely for lubrication.

    Aviation Engines

    Victor Wilfred Pag

British Dictionary definitions for castor oil

castor oil

  1. a colourless or yellow glutinous oil obtained from the seeds of the castor-oil plant and used as a fine lubricant and as a cathartic
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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

castor oil in Medicine

castor oil

  1. A colorless or pale yellowish oil extracted from the seeds of the castor-oil plant, used pharmaceutically as a laxative and skin softener and industrially as a lubricant.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.