What is Judicial Officer?

Legal Definition
A Judicial officer is a person with the responsibilities and powers to facilitate, arbitrate, preside over, and make decisions and directions in regard to the application of the law.

Judicial officers are typically categorized as judges, magistrates, puisne judicial officers such as justices of the peace or officers of courts of limited jurisdiction; and notaries public and commissioners of oaths. The powers of judicial officers vary and are usually limited to a certain jurisdiction.
-- Wikipedia
Legal Definition
A person in whom is vested authority to decide causes or exercise powers appropriate to a court. Settle v. Van Evrea, 49 N. Y. 284; People v. Wells, 2 Cal. 203; Reid v. Hood, 2 Nott & McC. (S. C.) 170, 10 Am. Dec. 582.
-- Black's Law Dictionary
Legal Definition
A justice for the peace, magistrate, or judge or any other officer of the court.