What is the definition of an alien in the context of U.S. law?

In the context of U.S. law, the term "alien" specifically refers to any person who is not a citizen or national of the United States. This definition encompasses a wide range of individuals, including those who may be visiting, residing, or working in the U.S. temporarily or permanently, as well as those who may not have a legal status within the country.

This definition is significant as it establishes the legal framework for immigration, residency, and the rights and responsibilities that apply to non-citizens. Understanding this classification is crucial for various legal processes, including immigration enforcement, asylum applications, and the determination of benefits eligibility.

The other options provide more specific contexts that do not cover the holistic scope of what constitutes an "alien" under U.S. law. For instance, while the first option talks about citizens of other countries, it does not fully capture individuals who may have a stateless status or those who reside in the U.S. without any formal citizenship. The second option incorrectly includes U.S. citizens living abroad, who are not classified as aliens. The fourth option narrows down the definition to those who have entered the U.S. illegally, which is just a subset of the broader category of aliens. Overall, understanding the comprehensive