it means a state of extreme confusion and disorder. cowboy...

Zoeyever & Roi G have provided the most common & practical/useful definitions. I just wanted to add a native speaker's point of view. :)

Without any clue to the context, this ancient word has several meanings both for daily usage and 'scholarly dissertations' It means confusion and disorder at its top level; in this sense, and also due to its presence in the Bible meaning "the void before creation" it has also a meaning related to something new that will happen. Etymology: from the Greek 'chaos', with the meaning: 'abyss' Examples: Look at the chaos you turned your room into ! Stars, planets, Mankind, even Italki itself are here due to the ultra energetic photons in the primordial chaos, and to many other lucky circumstances. The seemingly chaotic dance of the bees near the hive actually have a precise meaning.

unpleasant sounds, messy situation.

What chaos?