Real Dictionary

bean
Beans such as coffee beans or cocoa beans are the seeds of plants that are used to produce coffee, cocoa, and chocolate.
Beans such as green beans, French beans, or broad beans are the seeds of a climbing plant or the long thin cases which contain those seeds.
Beans such as soya beans and kidney beans are the dried seeds of a bean plant.
countable noun: Beans are baked beans.

bean in American English
any of various leguminous plants; esp., any of several species of a genus (Phaseolus) of the pea family, including the kidney bean and lima bean
noun: the edible nutritious seed of various plants of the legume family, esp. of the genus Phaseolus

bean in British English
noun: any of various leguminous plants of the widely cultivated genus Phaseolus producing edible seeds in pods