> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getcollate.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Import an OWL/SKOS Ontology | Collate Knowledge Graph Guide

> Import an OWL or SKOS ontology into an existing glossary as glossary terms and typed relations.

# Import an OWL/SKOS Ontology

Import an existing Web Ontology Language (OWL) or Simple Knowledge Organization System (SKOS) ontology into a Collate glossary. Collate converts the ontology's concepts, classes, and relationships into glossary terms and typed relations.

## Before You Begin

* Create the target glossary before importing the ontology.
* Confirm that you have **Edit All** permission for the glossary.
* Ask an administrator to run the import if the ontology introduces relation types or custom properties that don't already exist in Collate.

## Supported Formats

Collate supports the following Resource Description Framework (RDF) serializations:

| Syntax | File Extensions |
| - | - |
| Turtle | `.ttl`, `.owl` |
| RDF/XML | `.rdf`, `.xml`, `.owl` |
| N-Triples | `.nt` |

Collate detects whether an `.owl` file uses Turtle or RDF/XML syntax from the file contents.

## Importing an Ontology

1. In the left navigation menu, select **Governance** > **Glossary**.
2. Open the glossary that will contain the imported ontology.
3. Click the **⋮** icon and select **Import Ontology**.
4. Upload the ontology file. Collate validates the file without changing the glossary and displays a summary of the terms, relations, mappings, and properties it found.
5. Review the validation summary and resolve any reported issues.
6. Click **Import**.

## What Gets Imported

| Ontology Construct | Becomes |
| - | - |
| `skos:Concept` or `owl:Class` | A glossary term |
| `skos:broader` or `rdfs:subClassOf` | The term's parent in the glossary hierarchy |
| `skos:closeMatch`, `skos:exactMatch`, and other `skos:*Match` properties | A concept mapping on the term |
| `owl:ObjectProperty` edges | A typed related term |

If RDF indexing is enabled, Collate automatically mirrors imported glossary terms into the RDF triplestore. For more information, see [RDF Knowledge Graph Indexing](/ai-2-0/admin-guide/applications/rdf-indexing-overview).

## Using the API

To automate an import, send the ontology file's contents to the following endpoint:

```text theme={null}
PUT /api/v1/glossaries/name/{glossaryName}/importRdf
```

| Query Parameter | Values | Default |
| - | - | - |
| `format` | `turtle`, `rdfxml`, `ntriples` | `turtle` |
| `dryRun` | `true`, `false` | `true` |

Set the `Content-Type` header to `text/turtle`, `application/rdf+xml`, or `application/n-triples` to match the file's syntax. Run the request with `dryRun=true` first, review the response, and then set `dryRun=false` to persist the import.

```bash theme={null}
curl -X PUT "$COLLATE_HOST/api/v1/glossaries/name/product-taxonomy/importRdf?format=turtle&dryRun=false" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: text/turtle" \
  --data-binary @taxonomy.ttl
```

The response reports the terms created or updated, relations and mappings added, relation types registered, custom properties created, and any warnings generated during the import.

<Card title="Ontology Explorer" href="/ai-2-0/how-to-guides/data-governance/ontology">
  Visualize the imported terms and their relationships as a graph.
</Card>


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