If you're like me and enjoy a bit of trivial 'word nerd' fun, check this out from the lovely folks at Merriam-Webster.com: How a Word for a Void Came to Mean a Confused MassA mad dash, a big scrum, a muddled jumble — all of it could be described with one word: chaos. Our most common uses of chaos today imply either a confused mass or jumble of things, or a state of utter confusion. But when chaos first entered English, it referred to the inverse of confusion: chaos first referred to a void.
Later, in the 1600s, there was renewed interest in the Classical authors, and that's when chaos gained its more familiar sense. Ovid, the great Roman thinker, thought of chaos as not a formless void from which all things were made, but as a formless, jumbled, disorganized mass. English speakers borrowed this meaning of chaos, then broadened it into the word we recognize today: one that denotes utter confusion or disorganization.