castor oil

noun

: a pale viscous fatty oil from castor beans used especially as a cathartic and as a lubricant and plasticizer

Examples of castor oil in a Sentence

Recent Examples on the Web

Applying just a few drops of castor oil in your hair at a time is best. —Brittany Lubeck, Verywell Health, 4 June 2025

This highly concentrated serum is packed with not just castor oil, but a variety of hair density-boosting peptides. —Jenn Barthole, Glamour, 28 May 2025

Others apply the castor oil to a piece of cloth or cotton ball and leave it in their belly button overnight, wrapping their torso with a larger piece of cloth (known as a castor oil pack) to keep it in place. —Justin Laube, EverydayHealth.com, 28 Apr. 2025

Calabrian bergamot and orange oil), this cuticle-sealing formula hydrates strands from the inside out, recalibrating elasticity and moisture via a blend of butters, aloe vera, and castor oil. —Annie Blackman, Allure, 25 May 2025

Word History

Etymology

probably from its former use as a substitute for castoreum in medicine

First Known Use

1746, in the meaning defined above

Rhymes for castor oil

• aerofoil
• cinquefoil
• hydrofoil
• quatrefoil
• airfoil
• benzoyl
• despoil
• embroil
• etoile
• gargoyle
• recoil
• subsoil

Kids Definition

castor oil

noun

: a pale thick oil obtained from castor beans and used chiefly as a lubricant or a laxative

Medical Definition

castor oil

noun

: a pale viscous fatty oil from castor beans used especially as a cathartic or lubricant