PloneOntology is an ontology based replacement for the existing keyword mechanism in Plone.

PloneOntology collaboratively maintains a relationally structured vocabulary of keywords for content classification, searching and navigation. The terms of the vocabulary are networked by arbitrary relationships and thus form a thesaurus for an ontology. In addition to the hierachical parent/child relationships found in taxonomies also e.g. synonyms, antonyms or translations may be referenced.

• Find directly and more distantly related content.
• Navigate through content by keywords and their relations.
• Relation graph visualization with Graphviz.
• Keyword and relation names from the unicode character set.
• Collaboratively build, extend  and manage ontologies with the CMS tools within Plone, as the keywords are Archetypes content objects.
• Terms and relations to other terms may be proposed by users and peer-reviewed and decided upon by dedicated reviewers through a workflow.
• Allowed relation names for users to choose from (parent, child, synonym, etc.) are defined as a site policy.
• Relation properties such as inversity, symmetry or cardinality may be specified and are automatically maintained by Relations.
• OWL import/export of the ontology.