Disorder MD confused with pneumonia (11)

I believe the answer is:

pandemonium

'disorder' is the definition.
(I know that disorder can be written as pandemonium)

'md confused with pneumonia' is the wordplay.
'confused with' indicates an anagram.
'md' mixed up with 'pneumonia' gives 'PANDEMONIUM'.

(Other definitions for pandemonium that I've seen before include "havoc" , "Tumultuous uproar" , "Chaos and confusion" , "State of chaos" , "Bedlam" .)

I've seen this clue in The Times and The Sunday Times.

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