I'm writing game worlds and I've started working on representing the worlds not just as text and images but as a graph of topics and associations. In other words, an ontology representing the game world's characters, places, events, concepts, terms and so on.
Where I've got a bit stuck is in defining and naming the relationships between topics. It's easy enough to come up with things like "is a", "part of", "located in" etc, but as the work goes on, I realize that using the terms loosely will not work well, there are many relationships that overlap in meaning and you start wondering if this hasn't already been done. I've looked into OWL for creating ontologies, and topic maps, but what I lack is an actual data set of named associations (predicates in RDF) that I can build on, that have been vetted and used for larger projects.
What is a good strategy and resource to describe relationships between concepts in an ontology?