Wiktionary

Wiktionary is a sister project of Wikipedia, created by the Wikimedia Foundation with the goal of creating and distributing a free, open-content dictionary and thesaurus under the GFDL. It began operation on December 12, 2002.

Wiktionary is a compound word made up of the words wiki and dictionary.

The Japanese version of Wiktionary has a more difficult editing policy than Wikipedia, so the number of articles is not increasing. The reason for this will be explained later. However, links from Wikimedia projects, including Wikipedia, can use simple descriptions in Wikigrammar called interwikilinks, regardless of the language version. (For details, see Editing pages, Interlanguage links, etc.)

Wiktionary was initially an English-based dictionary with all explanations in English. Dictionaries in each language were prepared in parallel, and on May 1, 2004, it began working in other languages.

As of April 2007, it is available in 172 languages. The English version has the most items, followed by the French and Vietnamese versions.