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