Quite out of order (7)

I believe the answer is:

chaotic

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'out of order' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for chaotic that I've seen before include "badly arranged" , "Anarchic" , "In total disorder" , "mess" , "Riotous" .)

I've seen this clue in The Globe and Mail.

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