WordNet is a database of English words, which includes semantic relationships of words too. It includes synonym and antonym-relationships, as well as "categories". For example, it will tell me that a tabby is a cat and that a cat is an animal.
Is there anything comparable for Chinese, which is freely downloadable?
Anything that can be used online is already useful, but I'd prefer a database that I can download and analyse on my own computer. I only need it for personal use (in case the license doesn't allow anything else).