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

Ricin is a highly toxic poison naturally derived from castor oil plants.

From BBC • Oct. 29, 2024

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

Look for products that contain petroleum jelly, castor oil and glycerin, Rogers said.

From Seattle Times • Feb. 5, 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

At night, your mother makes you drink castor oil, which she says tastes better than a green guava.

From "When I Was Puerto Rican" by Esmeralda Santiago