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This page is a proposal for a new Wikimedia Foundation Sister Project.
Status Under discussion
Reason A request for comment for adopting OmegaWiki is open.
What is the proposed name for the project? OmegaWiki
Proposed project tagline A dictionary in all languages
Project description
What is the project purpose? What will be its scope? How would it benefit to be part of Wikimedia?
How many wikis?
Will there be many language versions or just on one multilingual wiki?
How many languages?
Is the project going to be in one language or in many?
Proposed project website address
Proposed logo for the project logo
Technical requirements
If the project requires any new features that the MediaWiki software currently doesn't have, please describe in detail. Are additional MediaWiki extensions needed for the project?
Development wiki OmegaWiki
Interested participants Users

Translation projects
New sites
Meta projects
Babel - Babylon
Translation requests

OmegaWiki ( is a multilingual dictionary whose aim is to describe all words of all languages with definitions in all languages. The data is stored in a relational database.[1] It runs on WikiLexicalData, an extension of MediaWiki.

The key idea of OmegaWiki is to be based around concepts (called DefinedMeaning) rather than around words (called Expression).

Proposal: That the Wikimedia Foundation approve adopting the OmegaWiki project and allocate resources to support any technical aspects of migrating this project to Wikimedia servers. The project would continue to complement the work done on Wiktionaries, and to provide potential models for a Wikidata-backed multilingual dictionary.

The proposal can be discussed on the page Requests for comment/Adopt OmegaWiki



  • This proposal is being made by Gerard Meijssen, the founder of OmegaWiki project, and Kip, the current maintainer of OmegaWiki.
  • The majority of OmegaWiki contributors are in favor of the WMF supporting OmegaWiki [1].

Features of OmegaWikiEdit


For WikimediaEdit

  1. By being brought into the family of Wikimedia projects, OmegaWiki could raise the quality of Wiktionaries.
  2. In particular, translation tables could be managed centrally on OmegaWiki, instead of being duplicated over more than 100 Wiktionaries, similarly to how Wikidata works for interwiki links.
  3. There are Wiktionaries in 170 languages. Someone who wants to edit in a new language needs to start an active community and request for opening a new project. In OmegaWiki, definitions can be added in more than 400 languages already. Adding a new one is very easy.
  4. There is already a mapping between concepts in OmegaWiki and Wikidata. By using this mapping, Wikidata could obtain multilingual definitions for their items.
  5. OmegaWiki can be used to enhance the multilingual capabilities of Commons.

For OmegaWikiEdit

  1. Reputation of the Wikimedia movement might increase the editor base.
  2. More editors means potentially more programmers and more features.
  3. Would increase the reliability of the site, as is currently privately hosted on a poorly performing server.

Merging with WikimediaEdit

Server hostingEdit

The WMF could host OmegaWiki on its servers. The current server on which OmegaWiki is hosted [3] has only 1GB RAM which is very limiting. Response time could be improved, perhaps by separating the application server from the Web server, or by improvements in the software.

A server for OmegaWiki would require:

  • at least 2GB RAM, since the current SQL database is about 750MB.
  • PHP, MySQL and anything else that is needed to run MediaWiki 1.20 and some extensions.

Moving to a different server requires someone with access to the server (Kip or Erik), who would perform a full dump of the database and transfer it in the new server. The procedure for installing a copy of OmegaWiki is described there.

By moving the database, the old server would be switched off (since there would be no one left to maintain it), so that the website name "" - which belongs to GerardM - could be reused.

Other considerationsEdit


OmegaWiki already uses InstantCommons (i.e. images are taken directly from Wiki Commons), so that there are only a few images that would need to be transfered, which are screenshots of OmegaWiki illustrating the help pages.


OmegaWiki is already using translatewiki for its localization. Some other localization is done by the Wiki itself: in a translation dictionary, you can find translations for your own interface :)


OmegaWiki licences are CC-BY and GFDL. Both licenses are not compatible [4]. Since we want that as many people as possible can use the data from OmegaWiki, it was decided to dual-license it, so that people using our data can choose the license that suit them.

  • Licensing should probably stay CC-BY, not CC-BY-SA. There is a legal problem of copyrighting words, phrases, sentences and definitions, which mean that it would be probably better to leave the least restrictive license as the OmegaWiki license.

Unified LoginEdit

Most (if not all) of the contributors to OmegaWiki already have an account in a Wikimedia website, so that switching to Unified Login could be done without too much trouble.

Coexistence with WiktionaryEdit

OmegaWiki would coexist with the various Wiktionaries, and for several reasons:

  • While OmegaWiki is better for translations - because of how it is designed -, it seems that Wiktionary will still be a better tool for monolingual dictionaries, in particular because it is a Wiki page with no constraint.
  • Some Wiktionaries (e.g. English and French) have built a strong community. Forcing them to move to a different project would make no sense.
  • At the moment, OmegaWiki does not have all the features that Wiktionary provides (inflexion tables, etc.). Therefore it cannot be considered as a replacement.

However in the long term:

  • People editing Wiktionaries with a small community may voluntarily move to OmegaWiki, where edits would have more impact. (Many people of small communities already moved to the English Wiktionary for that reason). In that case, if a Wiktionary shows a lack of activity, it could be closed.
  • Translation tables in the various Wiktionaries could be replaced by data taken directly from OmegaWiki, similarly to how infotables at Wikipedia will be replaced by data taken from the Wikidata project.

Thus, Wiktionaries and OmegaWiki may well develop synergistically, each feeding the other.


Note that OmegaWiki already has (almost?) all the features to implement a multilingual Wikispecies. OmegaWiki has translations, hypernyms/hyponyms, images, and for concepts identified as animals, there are additional annotations to indicate its Genus, Ordo, Phylum, etc. See for example Canis lupus. Wikispecies could be merged into OmegaWiki, or the same software (WikiLexicalData extension) could be reused there, with little adaptations to meet the contributors' needs.

However, merging with Wikispecies is not in the scope of the present proposal. This should be discussed and decided by the contributors of Wikispecies.

Related projects/proposalsEdit

Similar proposalsEdit

The idea of a relational database for storing dictionary entries comes up every now and then. Many of them are opposed for the reason that "OmegaWiki" already exists. So, the logical conclusion would be that OmegaWiki becomes an official Wikimedia project...

Similar sites (non-Wikimedia)Edit

  • The Kamusi project, similarly to OmegaWiki, is a multilingual dictionary based around concepts. It mostly focuses on African languages. It is free to edit. The data is licensed under CC-By-SA-NC 3.0.
  • Wordnet is an English dictionary/ontology based on concepts (synsets). The data is free, but cannot be edited, and the compatibility of their home-made license with CC-By is uncertain.
  • FreeDict is a collection of bi-lingual dictionaries in a shared format, the TEI.

See alsoEdit

Possible uses:


  1. In OmegaWiki, the different lexical and semantical data about a word, such as the word itself, its definition, its translations, its part of speech, etc. are stored in separate tables of a relational database. The current structure is explained at

External linksEdit