- A plant with leaves that have high levels of the addictive chemical nicotine.
After harvesting, tobacco leaves are cured, aged, and processed in various ways. The resulting products may be smoked (in cigarettes, cigars, and pipes), applied to the
gums (as dipping and chewing tobacco), or inhaled (as snuff). Cured tobacco leaves
and the products made from them contain many cancer-causing chemicals, and
tobacco use and exposure to secondhand tobacco smoke have been strongly linked to
many types of cancer and other diseases. The scientific name of the most common
tobacco plant is Nicotiana tabacum.