To answer the question if the Geohealth domain requires a body of knowledge (BoK), we need a general understanding of concepts associated with this field. Two years ago, the United Nation (UN) committee of experts on global geospatial information management identified "semantic- and ontology-linked data" as something that "will become essential to support the next generation of autonomous systems" (UN-GGIM, 2020). The term ontology is closely related to BoK. Unlike data models, ontologies are independent of application; they are generic, can be used in different ways and have clear advantages but they are challenging to create and even more difficult to maintain. The brief description below summarizes what ontologies are, why they are needed to support linked data, what the role of the semantic web is, what is already going on within the Geohealth domain on ontologies and how a BoK can assist.