menthol, white crystalline substance with a characteristic pungent odor. It is derived from the oil of the peppermint plant, Mentha piperita (see mint), or prepared synthetically from coal tar. An alcohol, menthol is freely soluble in ethyl alcohol, ether, and chloroform. It is a local anesthetic and helps relieve itching, and because it imparts a tingling sensation to the skin, it is used in after shave lotions and skin fresheners. It is also used in throat lozenges, inhalers, and as a flavoring.

Crystalline organic compound of the isoprenoid family. It has a strong, minty, cooling odour and taste. It is obtained from the oil of the Japanese mint or made synthetically and is used in cigarettes, cosmetics, chest rubs, cough drops, toothpastes, and flavourings. Of its two optical isomers (see optical activity; isomerism), only l-menthol has the desirable cooling effect.

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