Another project of the Wikimedia Foundation.
Wiktionary, a collaborative project to produce a free multilingual dictionary in every language, with definitions, etymologies, pronunciations and quotations. Wiktionary is the lexical companion to the open-content encyclopedia Wikipedia. In the English edition, started on December 12, 2002, we are now working on 120518 entries.
As of 2006-02-11, the french wiktionary is now the biggest, see List of largest wiktionaries.