<a href="http:&#x2F;&#x2F;dico.isc.cnrs.fr&#x2F;dico&#x2F;en&#x2F;search" rel="nofollow">http:&#x2F;&#x2F;dico.isc.cnrs.fr&#x2F;dico&#x2F;en&#x2F;search</a><p>I use this for both English and French synonyms. Fast, light and all words are hyperlinked. It does not provide definitions but uses scientific methods to establish synonyms.