essential oil

noun

: any of a class of volatile oils that give plants their characteristic odors and are used especially in perfumes and flavorings, and for aromatherapy compare fixed oil

Examples of essential oil in a Sentence

Recent Examples on the Web

The Bermuda Blue Citrus was available in unique cleaning, laundry, and air-freshening items, including a fragrance booster, laundry detergent sheets, fabric softener dryer sheets, an essential oil refill, and a solid air freshener gel. —Rebecca Jones, Southern Living, 28 Oct. 2025

Tea tree oil is a potent essential oil. —Heidi Cope, Health, 27 Oct. 2025

Rosemary Clary Sage Hand Soap Like the tomato soap, this option is made with 100% essential oils that offer a pleasant fragrance that isn’t overpowering. —Jacqueline Tempera, Better Homes & Gardens, 24 Oct. 2025

According to De La Torre, rosemary essential oil is as effective as minoxidil in a study comparing the two interventions used for six months, with rosemary oil having fewer side effects like the scalp itching associated with topical medications. —Essence, 23 Oct. 2025

Word History

First Known Use

1674, in the meaning defined above

Rhymes for essential oil

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

Medical Definition

essential oil

noun

: any of a large class of volatile odoriferous oils of vegetable origin that give plants their characteristic odors and often other properties, that are obtained from various parts of the plants (as flowers, leaves, or bark) by steam distillation, expression, or extraction, that are usually mixtures of compounds (as aldehydes or esters), and that are used often in the form of essences in perfumes, flavorings, and pharmaceutical preparations

called also ethereal oil, volatile oil

compare fatty oil, fixed oil