Lady in far off fantasy world (9)

I believe the answer is:

fairyland

'fantasy world' is the definition.
('fairyland' can be a synonym of 'fantasy world')

'lady in far off' is the wordplay.
'off' indicates anagramming the letters.
'lady'+'in'+'far'='ladyinfar'
'ladyinfar' is an anagram of 'FAIRYLAND'.

(Another definition for fairyland that I've seen is " fabulous state".)

I've seen this clue in The Telegraph.

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