The definition of brain drain refers to a situation where all or the majority of intelligent, skilled or capable resources within a given field or geographic region leave the area because of various factors including lack of high paying jobs.(noun)
An example of brain drain is when almost all people who are highly educated but who live in a third-world country find jobs in the US and leave their home country.
See brain drain in Webster's New World College Dictionary
See brain drain in American Heritage Dictionary 4
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