Can someone please tell me why Amir Khan's character is named PK in his Bollywood film, PK?
PK is a hindi slang. It expands as 'Pea kay' and it means being drunk. Whenever Amir Khan's character talks to the general people, they feel like his statements and questions are absurd and idiotic. So they ask him whether he is drunk (PK), and hence he gets this name.
It's comical usage of the name PK, which is a common name as Pankaj Kumar or Prashant Khare and so on, also means drunk. When he asks questions to people which seem absurd to a common man, they ask if he is drunk (bhai pi ke he ka). And continuosly being asked the same Amir Khan eventually starts believing that maybe he is known as PK on earth, somehow earth people know but he doesn't.