Para traducir en Linux
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Yo utilizo WORDTRANS y me parece que es bueno ...
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Si quieres un "dicionario" offline (aunque para actualizar si necesitas estar conectado) yo utilizo.. JDictionary (http://jdictionary.sourceforge.net )... caracteristicas del software...tomado de su site:
Dictionary has a nice and intuitive user interface. You will understand the whole concept at once. jDictionary is able to upgradeitself, upgrade its plugins, provide news and information about newplugins. Downloading and installing a new plugin is just one click.Platform IndependentThat means you can run jDictionary on Windows, Linux, Solaris, Mac andso on. All features work in the same way on each platform.Plugin BasedjDictionary is plugin based and has an easy to use plugin managementsystem which is able to download and install the desired pluginsautomagically from the web. Installing or upgrading one or moreplugins (even simultaneously) is just one click!There are more and more plugins available for jDictionary. It's notnecessary for a plugin to be a dictionary related stuff. For example,currently there is a speech synthesizer plugin under development whichwill be invoked by other plugins to pronounce the desired words.FreejDictionary is licensed under the LGPL license, so you can downloadand use this program for free, and download its source code too.Download: http://jdictionary.sourceforge.net/download.html