[1] : The Collaborative International Dictionary of English v.0.48

lactone \lac"tone\, n. chem.
   one of a series of organic compounds, being cyclic esters
   which may be regarded as anhydrides of certain hydroxy acids.
   in general, they are colorless liquids, having a weak
   aromatic odor. they are so called because the typical lactone
   is derived from lactic acid.
   1913 webster

Lactone >> L Words
Lactone, definition of term: Lactone
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