Definition of ester in English:

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Pronunciation: /ˈestər/


An organic compound made by replacing the hydrogen of an acid by an alkyl or other organic group. Many naturally occurring fats and essential oils are esters of fatty acids.
Example sentences
  • Fatty acid methyl esters were analyzed by gas chromatography as described above.
  • Fatty esters help replace natural esters missing from older, dryer skin types.
  • The ester ethyl acetate can be produced using either an organic or inorganic acid.



Pronunciation: /əˈsterəˌfī/
verb (esterifies, esterifying, esterified)
Example sentences
  • In that study it was postulated that the reduction of unsaturated fatty acids esterified in lipids was of no significance as a mechanism of plant adaptation to anaerobic conditions.
  • In addition, unsaturated fatty acids esterified in lipids may also accept protons under anaerobic stress.
  • Under normal physiologic conditions, the heart's preferred fuels are fatty acids, esterified as triglycerides and lactate.


Mid 19th century: from German, probably from a blend of Essig 'vinegar' and Äther 'ether'.

Words that rhyme with ester

arrester, Avesta, Chester, contester, Esther, fester, fiesta, Hester, investor, jester, Leicester, Lester, molester, Nestor, pester, polyester, protester, quester, semester, sequester, siesta, sou'wester, suggester, tester, trimester, vesta, zester

For editors and proofreaders

Syllabification: es·ter

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