Definition from Wiktionary, the free dictionary
|simpl. and trad.|
老外 (traditional and simplified, Pinyin lǎowài)
- (colloquial) foreigner
- (figuratively) a Chinese person who acts western or does not understand a specific topic related to Chinese culture
Usage notes 
Using the term to refer to foreigners is controversial and may be perceived as exclusionist. It is usually not dergoatory.