mustard oil

American  

noun

1. oil expressed from the seed of mustard, used chiefly in making soap.

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mustard oil British  

noun

1. an oil that is obtained from mustard seeds and used in making soap

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Etymology

Origin of mustard oil

First recorded in 1840–50

Example Sentences

"Other natural ingredients, such as mustard oil, or the topical medication imiquimod are known to also stimulate the TRPA1 receptor, but unlike rosemary, those can cause irritation and inflammation."

From Science Daily • Dec. 7, 2025

Coconut and mustard oil are a stellar combination here, as the sweetness of the coconut tempers the bitterness of the mustard oil and seeds.

From Seattle Times • Apr. 30, 2023

The bitter sulfurous compounds are part of a Brussels sprouts' sophisticated defense system, known as the mustard oil bomb, that repels insects from biting them but attracts those insects that allow pollination.

From Salon • Dec. 25, 2022

Luscious chunks of pork, crisp from their time in a clay oven, resonate with mustard oil, ginger and garlic.

From Washington Post • May 13, 2022

Just before we lay down to sleep, Mrs. Lai gave Sass some mustard oil and camphor to rub on Hari’s chest.

From "Homeless Bird" by Gloria Whelan