English Reference

Word

ester

Phoneticses·ter

US/ˈɛstɝ/

UK/ˈɛstɐ/

Definition

n. a chemical compound that often has a pleasant, fruity smell. You find these in nature in fruits and flowers, and they are also used to make artificial flavors and perfumes.

n. an organic compound formed by the reaction between an acid and an alcohol, typically with the elimination of water. Characterised by a carbon atom double-bonded to an oxygen atom and single-bonded to an alkoxy group.

Examples

“The sweet smell of a banana comes from an ester.”

“Chemists often synthesise specific esters in the lab to create artificial scents for soaps and candles.”

“In organic chemistry, the process of esterification involves a carboxylic acid reacting with an alcohol in the presence of an acid catalyst to produce an ester and water.”

Examples

simple

“The sweet smell of a banana comes from an ester.”

contextual

“Chemists often synthesise specific esters in the lab to create artificial scents for soaps and candles.”

complex

“In organic chemistry, the process of esterification involves a carboxylic acid reacting with an alcohol in the presence of an acid catalyst to produce an ester and water.”

Usage

Often used in the plural when referring to a class of compounds or various scent profiles.

Real-World Examples

“Ideally, this would involve using only polymers with biochemical breaking points , such as the hydrolyzable ester bonds in polyesters like LCAP or other types of bioplastics," concludes Schleheck.”
Phys.org · 2 Sept 2026
“But in the case of functional groups such as esters, skeletal editing remains difficult because their carbon–carbon and carbon–oxygen bonds are resistant to cleavage under mild conditions.”
Phys.org · 30 Aug 2026

This entry

Level
C2 · Proficiency
Frequency
Occasional
Updated

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English Reference