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poisonous alkaloid found in tobacco leaves, 1819, from French nicotine, earlier nicotiane, from Modern Latin Nicotiana, formal botanical name for the tobacco plant, named for Jean Nicot (c.1530-1600), French ambassador to Portugal, who sent tobacco seeds and powdered leaves back to France 1561. His name is a diminutive of Nicolas.
nicotine nic·o·tine (nĭk'ə-tēn')
A colorless, poisonous alkaloid derived from the tobacco plant and used as an insecticide. It is the substance in tobacco to which smokers can become addicted.
A poisonous chemical substance found in the tobacco plant.