ester

American  

[es-ter] / ˈɛs tər /

noun

Chemistry.

• esters
  plural

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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Other Word Forms

Noun Inflected Forms

• esters
  plural

Etymology

Origin of ester

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

Example Sentences

See Examples For:

ester esters

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

From Science Daily ● Jan. 24, 2024

The team's first step was to identify the gene in large black chafers for the receptor that reacts to the female pheromone, which has the seductive name L-isoleucine methyl ester, or LIME.

From Science Daily ● Jan. 18, 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

In the ester linkage, the first carbon in the fatty acid chain has an oxygen double-bonded to it, whereas in the ether linkage, it does not.

From Textbooks ● Jan. 1, 2015

We may note here that an important item in the quantitative factors of the cellulose nitric ester reaction has been overlooked: that is, the yield calculated to the NO3 groups fixed.

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

The team designed a three-step, activity-focused process to uncover bioactive diterpene esters in roasted Coffea arabica beans.

From Science Daily ● Jan. 11, 2026

Once the water is cleared, chemical groups called NHS esters embedded in the polyacrylic acid form strong bonds with proteins at the tissue surface.

From Science Daily ● May 22, 2024

The researchers began by synthesizing menthyl esters of six amino acids characterized by less-reactive side chains.

From Science Daily ● May 15, 2024

"There are five fruit esters, or aroma compounds, which are very typical for Heineken, and we know which ones to bring back," says Mr van Waesberghe.

From BBC ● Feb. 15, 2024

Ligno-celluloses.—These compounds have many of the characteristics of the cellulose esters; they are in effect ethereal compounds of cellulose and the quinonoid lignone complex, and the combination resists hydrolysis by weak alkalis or acids.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5 "Cat" to "Celt" by Various