oleic acid

American  

noun

Chemistry.

1. a colorless, odorless, liquid, water-insoluble, unsaturated acid, C 1 8 H 3 4 O 2 , obtained from animal tallow and natural vegetable oils, in which it occurs as the glycerol ester: used chiefly in the manufacture of soap, commercial oleates, and cosmetics.

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oleic acid British  

/ əʊˈliːɪk /

noun

1. Systematic name: cis-9-octadecenoic acid.  a colourless oily liquid unsaturated acid occurring, as the glyceride, in almost all natural fats used in making soaps, ointments, cosmetics, and lubricating oils. Formula: CH 3 (CH 2 ) 7 CH:CH(CH 2 ) 7 COOH

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oleic acid Scientific  

/ ō-lē′ĭk /

1. An oily liquid occurring in animal and vegetable oils and used in making soap. Chemical formula: C ₁₈ H ₃₄ O ₂ .

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Etymology

Origin of oleic acid

First recorded in 1810–20

Example Sentences

One area of focus has been high-oleic soybeans, which are rich in oleic acid, a naturally occurring fatty acid found in animal and plant-based fats and oils.

From Science Daily • Jan. 18, 2026

The primary fat is oleic acid, a monosaturated fatty acid, which is also present in olive oil and is believed to bestow numerous health benefits.

From Washington Times • Jul. 15, 2016

About 40% of red palm oil is oleic acid, an unsaturated fat present in higher quantities in olive oil and believed to be part of the reason for its heart benefits.

From The Wall Street Journal • Aug. 3, 2015

Long-chain organic ligands, such as oleic acid, are used in the synthesis of PbSe QDs to control growth kinetics, allow for stable colloidal dispersions, and passivate surface states through their metal-ligand chemistry.

From Science Magazine • Dec. 15, 2011

According as an oil contains oleic acid or olinic acid, it is termed a fatty or drying oil.

From The Art of Perfumery And Methods of Obtaining the Odors of Plants by Piesse, George William Septimus