n. [ From Lactuca. ] (Chem.) A white, crystalline, tasteless substance, found in the milky sap of species of Lactuca, and constituting an essential ingredient of lactucarium. [ 1913 Webster ]

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 ]

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 ]