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

These compounds are assembled from amino acid building blocks along with a conserved hydroxy acid pharmacophore, all connected through a combination of peptide and ester bonds.

From Science Daily ● Jul. 8, 2026

They created upcycled styrene ethylene butylene styrene copolymer, which incorporates boronic ester groups that covalently bond with a crosslinker and fibers to generate the tough CFRP.

From Science Daily ● Feb. 8, 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 an ester, the second oxygen atom bonds to another carbon atom.

From Textbooks ● Feb. 14, 2019

In practice it is not necessary to combine the saponification of cellulose ester with complete reduction of the nitric acid split off.

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

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

Organophosphate esters, or OPEs, gradually took their place.

From Science Daily ● Jan. 24, 2024

One group of such compounds was discovered in 1929 by W. Lange, who wrote: “Of interest is the strong action of mono-fluorophosphate esters on the human body—the effect is produced by very small quantities.”

From History of Phosphorus by Farber, Eduard