Nicotine \Nic"o*tine\ (? or ?), n. [F. nicotine. See
Nicotian.]
(Chem.)
An alkaloid which is the active principle of tobacco
(C10H14N2). It occurs in tobacco plants (Nicotiana
tabacum and Nicotiana rusticum) to the extent of 2 to 8%,
in combination with malic acid or citric acid. It is a
colorless, transparent, oily liquid, having an acrid odor,
and an acrid burning taste. It is intensely poisonous. The
apparently addictive effects of tobacco smoking have been
ascribed largely to the effect of nicotine, and the
controlled administration of nicotine on various forms has
been used as a technique for assisting efforts to stop the
smoking habit. --Ure.
[1913 Webster +PJC]
nicotine
noun1: an alkaloid poison that occurs in tobacco; used in medicine and as an insecticide
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