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late 14c., "process of distilling," from Late Latin distillationem (nominative distillatio), noun of action from past participle stem of distillare (see distill). Meaning "product of distilling" is from 1590s.
distillation dis·til·la·tion (dĭs'tə-lā'shən)
The evaporation and subsequent collection of a liquid by condensation as a means of purification.
The extraction of the volatile components of a mixture by the condensation and collection of the vapors that are produced as the mixture is heated.
A method of separating a substance that is in solution from its solvent or of separating a liquid from a mixture of liquids having different boiling points. The liquid to be separated is evaporated (as by boiling), and its vapor is then collected after it condenses. Distillation is used to separate fresh water from a salt solution and gasoline from petroleum. ◇ The condensed vapor, which is the purified liquid, is called the distillate.
In chemistry, the separating of the constituents of a liquid by boiling it and then condensing the vapor that results. Distillation can be used to purify water or other substances, or to remove one component from a complex mixture, as when gasoline is distilled from crude oil or alcohol from a mash. When water is purified by distillation, it is boiled in a container, and the steam is sent into cooling tubes. The steam is condensed and then collected as purified water in a second container. The impurities in the water are left behind in the first container and can be discarded.
Note: Figuratively, “distillation” is the process of retaining the essential features or components of something while removing nonessentials: “This book represents knowledge distilled from decades of research.”