Table of documentation contents

Custom embeddings



  • Custom words or abbreviations (i.e., “concepts”) can be added to Weaviate directly by extending the contextionary.
  • Transfer learning allows you to extend Weaviate in real-time.
  • A POST request to the RESTful endpoint /c11y/extensions is for extending the contextionary with custom concepts.
  • a GET request to the RESTful endpoint /c11y/concepts/{} returns if a concept is part of the Contextionary.


If you have a use case which contains particular words or abbreviations that Weaviate’s contextionary does not know, you can use the “extensions” endpoint to teach Weaviate the concepts in real-time.

Note that you need to learn Weaviate the new concepts before adding data.


An example of using the /v1/c11y/extensions endpoint to add or overwrite concepts:

POST /v1/c11y/extensions

  "concept": "buried lede",
  "definition": "The central element of an article mistakenly appearing deep in the text",
  "weight": 1

You can always check if a concept exists in the Contextionary:

GET /v1/c11y/concepts/{concept}

For example:

curl http://localhost:8080/v1/c11y/concepts/buriedLede

More Resources

If you can’t find the answer to your question here, please use the:

  1. Knowledge base of old issues. Or,
  2. For questions: Stackoverflow. Or,
  3. For issues: Github.
  4. For Frequently Asked Questions.
  • Contextionary
  • Synonyms