Skip to Content
Medical Term:


Pronunciation: to-bak'o


An herb of South American origin, Nicotiana tabacum, which has large ovate to lanceolate leaves and terminal clusters of tubular white or pink flowers. Tobacco leaves contain 2–8% of nicotine and are the source of smoking and chewing tobacco or snuff. Tobacco smoke contains nicotine, carbon monoxide (4%), nitric oxide, and numerous aromatic hydrocarbons and other substances known to be carcinogens, including benzo[a]pyrene, ß-naphthylamine, and nitrosamines.

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.