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

By peak summer, I harvest a karela for lunch daily, slice it into thin discs, smear mustard oil, turmeric, cumin with chili powder.

From Salon • May 9, 2026

"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

A meal begins with complimentary sel roti — rings of honey-sweetened rice bread — accompanied by a bowl of fermented daikon, slick with mustard oil and tossed with both mustard and fenugreek seeds.

From Washington Post • Aug. 24, 2021

I could hardly breathe for the smell of incense and the mustard oil burning in the hundreds of little lamps.

From "Homeless Bird" by Gloria Whelan