castor oil

American  

noun

castor oils plural

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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castor oil British  

noun

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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Other Word Forms

Noun Inflected Forms

• castor oils
  plural

Etymology

Origin of castor oil

1740–50; castor (perhaps variant spelling of caster ) + oil; perhaps so called because of its purgative effect

Example Sentences

See Examples For:

castor oil

The modified Arabidopsis overcame metabolic bottlenecks and produced significant amounts of an oil similar to castor oil that it doesn't naturally produce.

From Science Daily ● Apr. 30, 2024

Newer products include a hair strengthening collection with biotin and Jamaican castor oil, and a wig care collection that uses apple cider vinegar to remove build-up from weaves and wigs.

From Los Angeles Times ● Nov. 2, 2023

I even tried some of the suggestions you have offered: duct tape, tea tree oil, castor oil, iodine and vinegar soaks.

From Seattle Times ● Jan. 26, 2022

Now castor oil is staging a cosmetics comeback.

From Washington Post ● Feb. 14, 2020

“A doctor, for a child’s tummy ache? Nonsense. Some castor oil and a hot-water bottle will do just fine.”

From "The Interrupted Tale" by Maryrose Wood