essential oil

American  

noun

1. any of a class of volatile oils obtained from plants, possessing the odor and other characteristic properties of the plant, used chiefly in the manufacture of perfumes, flavors, and pharmaceuticals.

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essential oil British  

noun

1. any of various volatile organic oils present in plants, usually containing terpenes and esters and having the odour or flavour of the plant from which they are extracted: used in flavouring and perfumery Compare fixed oil See also oleoresin

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essential oil Scientific  

/ ĭ-sĕn′shəl /

1. Any of various volatile liquids, such as rose oil or lavender oil, that have a characteristic odor and are produced by plants. Essential oils are composed primarily of terpenes and of lesser quantities of alcohols, aldehydes, esters, phenols, and other compounds that impart particular odors or flavors. They are used to make perfumes, soaps, flavorings, and other products.

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Etymology

Origin of essential oil

First recorded in 1665–75

Example Sentences

Lin says, holding a bottle of green tea essential oil under my nose.

From Los Angeles Times • Jun. 11, 2025

With its earthy sweet scent, this essential oil also is used in the food industry and topically in various cosmetic preparations.

From Science Daily • Feb. 13, 2024

Switch between the sauna and the steam room, with the option to spritz the space with eucalyptus essential oil.

From Seattle Times • Jan. 20, 2024

For dispersion options, Sullivan recommends using a reed diffuser — sticks that soak up oil scents and emit aromas — or a mister-type diffuser that sprays the essential oil in water.

From Washington Post • Feb. 22, 2023

My cousin Kylie was working for my mother that day, filling vials of essential oil.

From "Educated" by Tara Westover