- A genus of leguminous plants (herbs, shrubs, or trees) of
many species, most of which have purgative qualities. The leaves of
several species furnish the senna used in medicine. - The bark of several species of Cinnamomum grown in China,
etc.; Chinese cinnamon. It is imported as cassia, but commonly sold as
cinnamon, from which it differs more or less in strength and flavor,
and the amount of outer bark attached.