A person who assigns names or terms to things, especially in a scientific or technical context. The nomenclator was responsible for naming the newly discovered species of plants.
An official or servant in ancient Rome who was responsible for announcing the names of people at public events. In ancient Rome, the nomenclator would accompany the politician to help him remember the names of important citizens.
A list or catalogue of names or terms, especially one compiled for reference in a particular field. Visitors can consult the museum's nomenclator of artifacts to learn more about each exhibit.