a person who comes from a foreign country; someone who does not owe allegiance to your country同义词：alien, noncitizen, outlander
someone who is excluded from or is not a member of a group同义词：outsider
形容词 foreign:
of concern to or concerning the affairs of other nations (other than your own)同义词：foreign
relating to or originating in or characteristic of another place or part of the world同义词：foreign, strange
not contained in or deriving from the essential nature of something同义词：alien, foreign
not belonging to that in which it is contained; introduced from an outside source同义词：extraneous, foreign
例句
The foreigner came to China and attended the Fair.外国朋友来华参加交易会。
She wedded a foreigner.她嫁给了一个外国人。
His broken English showed he was a foreigner.他的蹩脚的英语说明他是一个外国人。
He never met a foreigner who spoke such perfect Chinese.他从未见过中国话讲得这样纯正的外国人。
详细解释
for.eign.er n.（名词）One who is from a foreign country or place.外国人，外来者：从其它国家或地区来的人One who is from outside a particular group or community; an outsider.外人，局外人：某一组织或团体之外的人；局外人