|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|1.||having an external origin|
|a. developing or originating outside an organism or part of an organism|
|b. of or relating to external factors, such as light, that influence an organism|
|3.||psychiatry (of a mental illness) caused by external factors|
exogenous ex·og·e·nous (ěk-sŏj'ə-nəs)
Originating or produced outside of an organism, a tissue, or a cell.
Having a cause external to the body. Used of diseases.