What does ester mean?
An ester is a class of organic compound produced when an alcohol reacts with an acid, most commonly a carboxylic acid, replacing the acidic hydrogen with an organic group. Esters are among the most familiar chemicals in daily life even though few people know them by name: many carry strong, pleasant aromas, and specific esters are responsible for the characteristic smells of fruits such as bananas, pears, pineapples, and strawberries. For this reason they are widely used as artificial flavourings and fragrances, while larger esters such as fats and vegetable oils play essential biological roles. Esters also appear in materials science, forming the backbone of polyesters used in clothing and packaging. The term belongs primarily to the vocabulary of organic chemistry, biochemistry, perfumery, and food science. Understanding esters helps explain a striking fact of everyday experience: that a single class of compounds can account for so many of the natural and artificial scents we encounter.
nounA chemical compound formed by the reaction of an alcohol with an acid, in which the hydrogen of the acid is replaced by an organic group; esters typically have distinctive, often pleasant, fruity smells and are widely used in perfumes, flavourings, and plastics.
- A compound formed by the reaction of an acid (typically a carboxylic acid) with an alcohol, characterised by the general formula RCOOR′ and often having fruity odours.
"The ripe pear aroma of the wine comes from naturally occurring esters produced during fermentation."
"Chemists reacted the carboxylic acid with methanol to form the methyl ester."
"Many of the esters responsible for the scent of bananas and pineapples are added artificially to sweets and drinks."
Standard regular plural; used when discussing multiple compounds of this class.
"The fermentation produced several esters that gave the beer its fruity aroma."
The word 'ester' is a compressed piece of German chemistry: it was coined from 'Essig' (vinegar) and 'Äther' (ether), so every time you smell a synthetic fruit flavour, you're smelling something named after vinegar.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of ester
The word 'ester' was coined in mid-19th-century Germany as an abbreviation of 'Essigäther', literally 'vinegar ether', combining German 'Essig' (vinegar), from Latin 'acetum', with 'Äther'. The chemist Leopold Gmelin is generally credited with introducing the shortened form around 1848. English borrowed the term directly from German, and it has remained a standard technical term ever since. Its Latin root 'acetum' also underlies related English words such as 'vinegar', 'acetic', and 'acetate'.
How ester is actually used
A technical term used chiefly in organic chemistry, biochemistry, and the fragrance and food industries; it is neutral in register but rare in everyday conversation.
Easily confused with ester
An ester is a compound formed from an acid and an alcohol, whereas an ether is a compound linking two organic groups through an oxygen atom; the two are distinct classes despite the similar-sounding names.