To help users of our ontology understand this logic and use our chemical reaction class as intended, we would also want to provide a natural language definition as metadata. To preserve the direct reference to the other classes and relations mentioned in the formal definition, we would want to use their labels in this natural language definition. Hence, we could define our chemical reaction class informally along the lines of: "A process in which molecular entities of one or more chemical species with a reactant role are consumed and modified to produce molecular entities of one or more chemical species with a product role." This wording makes the related concepts in the Gold Book more explicit and the intended semantics are kept intact within the scope and ontological commitment of our ontology. We have thus mapped the meaning from the original natural language space of the Gold Book to the formal language space constituted by our hypothetical ontology.