Definition of "Foreign" :

adjective: relating to or originating in or characteristic of another place or part of the world

"Foreign nations."

adjective: of concern to or concerning the affairs of other nations (other than your own)

"Foreign trade."

adjective: not contained in or deriving from the essential nature of something

"The mysticism so foreign to the French mind and temper."

adjective: not belonging to that in which it is contained; introduced from an outside source

"Foreign particles in milk."