castor oil

American  

noun

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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Etymology

Origin of castor oil

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

Example Sentences

India mainly exports rice, shrimp, honey, vegetable extracts, castor oil and black pepper, while the US sends almonds, walnuts, pistachios, apples and lentils.

From BBC • Mar. 30, 2025

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

Jam went back to her hair, dabbing castor oil on her ends as she worked through a few tiny knots.

From "Pet" by Akwaeke Emezi