An ontologist (in Cyc-speak) is a Cyclist who focuses primarily on developing the Cyc Knowledge Base, aka the Cyc Ontology. Such individuals understand the structure of the Cyc KB and know how to express knowledge and queries in CycL. Thus, they know how to add new knowledge to Cyc, and how to ask questions of Cyc. Ontologists at Cycorp are familiar with the best practices for representing knowledge, and follow a query-driven development process.
Ontologists are also known informally as “OEers” and “ontological engineers,” though they are not officially engineers in the legal sense.