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acetoin

American  
[uh-set-oh-in] / əˈsɛt oʊ ɪn /

noun

Chemistry.
  1. a yellowish, pleasant-smelling liquid, C 4 H 8 O 2 , obtained from various carbohydrates, as glucose, by fermentation: used chiefly in the manufacture of flavors and essences.


Etymology

Origin of acetoin

aceto- + -in 2