Chaos

Even chaos has a pattern. You can see this as soon as you scan a patch of disheveled branches amongst unkept shrubs. Perhaps no discernable formula could predict the path of each branch beforehand--but a perceptive eye will notice that the apparent chaos has a pattern--else we would not be able to say that any of the branches are branches to begin with.

But it is easy to see patterns among the chaotic branching habits of living entities. But even the world of wind and stone has pattern. Though the clouds ever change in seemingly unpredictable ways... it is only for the shared properties (that manifest in repeating patterns through time) that we can continue to look up and declare that we see clouds.

So if ever it is found that chaos is a concrete property of the universe, it's likely to be less chaotic than the traditional meaning of the word would imply.