In law, the word "Alien" does not mean an extraterrestrial creature!
It simply means "Foreigner".
If a person is within a country's boundaries but does not hold its citizenship, they are legally an alien.
Step 1: Understand the legal concept. The term "alien" in law refers to a person's citizenship status in relation to a country they are present in or residing in. Step 2: Apply in the Indian context. An alien is a person who is NOT an Indian citizen but lives in or is present in India. Such a person owes allegiance to another country or state. Step 3: Eliminate wrong options. An Indian living abroad is an emigrant, not an alien. A tourist on a visa is a specific sub-category. The general definition is option (1). \[ \boxed{\text{not an Indian citizen but lives in India}} \]