[amarainn]

It is indeed for an international audience - language learners or people who are generally interested in learning about other languages and cultures.

There are various slang dictionaries for specific languages or countries, but as far as I could tell there were none taking slang from different languages and explaining it to foreigners.

Adding definitions in different languages would make the moderation process quite a bit more complicated, and it would also defeat the purpose of explaining slang to an external audience.