ester

American  

[es-ter] / ˈɛs tər /

noun

Chemistry.

1. a compound produced by the reaction between an acid and an alcohol with the elimination of a molecule of water, as ethyl acetate, C 4 H 8 O 2 , or dimethyl sulfate, C 2 H 6 SO 4 .

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ester British  

/ ˈɛstə /

noun

1. chem any of a class of compounds produced by reaction between acids and alcohols with the elimination of water. Esters with low molecular weights, such as ethyl acetate, are usually volatile fragrant liquids; fats are solid esters

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ester Scientific  

/ ĕs′tər /

1. An organic compound formed when an acid and an alcohol combine and release water. Esters formed from carboxylic acids are the most common, and have the general formula RCOOR|||PRIMARY_STRESS|||, where R and R|||PRIMARY_STRESS||| are organic radicals. Esters formed from simple hydrocarbon groups are colorless, volatile liquids with pleasant aromas and create the fragrances and flavors of many flowers and fruits. They are also used as food flavorings. Larger esters, formed from long-chain carboxylic acids, commonly occur as animal and vegetable fats, oils, and waxes. Esters have a wide range of uses in industry.

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Etymology

Origin of ester

First recorded in 1850–55; coined by L. Gmelin (1788–1853), German chemist

Example Sentences

Lovaza, a prescription medication containing the ethyl ester forms of EPA and DHA, is approved by the Food and Drug Administration to treat high triglyceride levels in the blood.

From Science Daily • Feb. 13, 2026

"Policy options to reduce exposure to organophosphate ester flame retardants should be considered."

From Science Daily • Jan. 24, 2024

Indonesia's B35 mandate, the highest in the world, stipulates diesel sold in the country from Feb. 1 has to contain 35% palm-based fatty acid methyl ester.

From Reuters • Jan. 13, 2023

Adenosine triphosphate, or ATP, is the primary energy currency in cells; ATP stores energy in phosphate ester bonds.

From Textbooks • Jun. 9, 2022

They confirm the probability of the occurrence of secondary changes in the ester reactions.

From Researches on Cellulose 1895-1900 by Cross, C. F.