Fantasy about the Queen wearing a crazy disguise (5)

I believe the answer is:

dream

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'fantasy' is the definition.
(I know that dream is a type of fantasy)

'about the queen wearing a crazy disguise' is the wordplay.
'about' says the letters should be written backwards.
'the queen' becomes 'ER' (Elizabeth Regina).
'wearing' is an insertion indicator.
'a crazy disguise' becomes 'mad' (I am not sure about this - if you are sure you should believe this answer much more).
'er' put inside 'mad' is 'maerd'.
'maerd' written backwards gives 'DREAM'.

Can you help me to learn more?

(Other definitions for dream that I've seen before include "Perfect" , "Illusion" , "Night-time fantasy" , "It's experienced during sleep" , "Nocturnal vision" .)

I've seen this clue in the Sydney Morning Herald.

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