The definition of adventitious is something added from outside or something that occurs by chance or accident.(adjective)
An example of adventitious is accidentally stumbling upon a cure for a disease while researching the components of a newly discovered plant.
See adventitious in Webster's New World College Dictionary
Origin: L adventicius, coming from abroad: see Advent
See adventitious in American Heritage Dictionary 4
Origin: From Latin adventīcius, foreign
Origin: , from adventus, arrival; see advent.
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