Sinonimi is an opensource software to search for synonyms in different languages.
It is designed to be integrated in a web portal, based on PHP 5.x or later.
Find synonyms via web browser
The search engine included in Sinonimi supports the following languages: italian, english, french, deutsch and espaņol. The user has to specify the word and the language, then press the search button to get all the synonyms related to a word.
The script supports also an automatic update of the web page, if no specific word was set.
Remote applications can retrieve synonyms using web interface that will return either XML or JSON results.
Here is a screenshot of the user interface: