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 .

---

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

---

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.

---

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

Although it resembled esterases, which are known for breaking down ester bonds, it also shared structural similarities with another important family of bacterial enzymes: beta-lactamases.

From Science Daily ● Oct. 16, 2026

In the largest study of its kind, researchers at UC Davis Health found that exposure to organophosphate ester flame retardants during pregnancy was associated with preterm birth, especially among females.

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

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 C. F. Cross

CR also looked at chemicals called glycidyl esters.

From Slate ● Sep. 14, 2026

The most concerning product that CR tested in terms of glycidyl esters was Takis Fuego tortilla chips.

From Slate ● Sep. 14, 2026

Driven by the discovery of LXR-SCD1 intracellular machinery, Prof. Arimura and his team hypothesized the menthyl esters to possess anti-obesity properties.

From Science Daily ● May 15, 2024

The menthyl esters showed exceptional anti-inflammatory and anti-obesity activities during preclinical studies and can be developed as therapeutic compounds with further research.

From Science Daily ● May 15, 2024

The natural fats, vegetable oils, and plant waxes are all esters.

From The Chemistry of Plant Life by Roscoe Wilfred Thatcher

Random Word

Spin the wheel and learn a new word!

---