so just to have a language tab that lists the languages there are terms for. or a way to search for terms in a language.

I think this is a good idea, but I think it would be much more helpful if you could make a way to search terms by language as well as popularity, new words, and by searching words.
when just browsing around your site its hard to stay interested in whats just on the first page.
when people are going to visit another place they might want to come here and see the common terms used there.