Late in Fall 2014 MIT intends to start an activity with forum users to translate some of the documentation to other languages. This means by 2015 there may be language resources available. Which languages will depend on how many volunteers are found to do the translations. Until then, many AI2 users whose language is not English use Google Translate -- it provides an imperfect translation but it is often useful. Also, there are some Web pages devoted to App Inventor in various other languages ... for example, do a Web Search for "App Inventor Spanish" and you get
https://sites.google.com/site/appinventormegusta/ Perhaps there are Web pages in your language?
To make a simple dictionary with AI2 I would use a List of Lists, then the lookup in pairs block (in the List blocks). You would want to have a search routine to find the word in your own language, once it is found, the app would find the corresponding word in English. The reverse is true also. Yes, you will also need a few buttons, textboxes (to input your search word) and labels (to display the corresponding words in English or your language).
Enis mentioned, this would have to be a small dictionary, but it might be all you want and a limited dictionary can be built with AI2.
What language would you use? Is this what you intend?
Regards,
Steve