Any individual within the country’s borders, who is not a U.S. citizen, is called an alien.
The term ‘alien’ can be used in reference to any person within the country’s borders, who is not a U.S. citizen. Aliens are classified in two broad categories – non-resident aliens and resident aliens. According to the IRS, an alien who does not meet either of the substantial presence test and the green card test is known as non-resident. For instance, fresh arrivals in the country on F-1 or J-1 visa are usually non-resident aliens.
Individuals who meet either the substantial presence test (physical presence in the country for over 31 days in a year and 183 days in 3 years) or the green card test are called resident aliens. For more information on aliens and employers on immigration cases, please visit the Department of Labor (DOL) website.
What Does the Term Alien Mean?