The Urban Dictionary: defo.

This is an interesting dictionary where you can find terms used by people everyday which are not easily found in more formal dictionaries. It works like Wikipedia and I find the definitions very helpful.

Try with these words: defo, oi or uber. I have heard them and seen them written very often, in the last case in articles and reviews in magazines.

I will add a link for easy access under the Vocabulary and Grammar entry in the column on the right.