What is the term for an assumed name that a person might use?

The term "alias" refers specifically to an assumed name that a person may use, often for purposes of concealment, anonymity, or to create a persona that is separate from their legal name. This term is commonly used in law enforcement and legal contexts to identify someone who may be operating under a different identity for various reasons, such as evading law enforcement or engaging in illegal activities.

While "pseudonym," "moniker," and "nickname" can all refer to alternative names, they have slightly different connotations. A pseudonym is typically used by authors and artists to protect their identity or for branding purposes, often associated with creative work. A moniker is a more casual term that can refer to any nickname or informal name someone might choose, and "nickname" specifically highlights a name that is usually given in an informal context or as a term of endearment. However, "alias" carries the strongest connotation of being an alternative identity used in more serious or clandestine situations, making it the best fit for the question regarding an assumed name.