Fictitious name

Definition of Fictitious name

A counterfeit, alias, feigned, or pretended name taken by a person, differing in some essential particular from his true name (consisting of Christian name and patronymic), with the implication that it is meant to deceive or mislead. See also Alias.

That's the definition of Fictitious name in Black's Law Dictionary 6th Edition. Courtesy of Cekhukum.com.