Bored, cynical attitude to planetary fatigue (5-9)

I believe the answer is:

world-weariness

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'bored cynical attitude' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.

'planetary fatigue' is the wordplay.
'planetary' becomes 'world' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'fatigue' becomes 'weariness' (feeling fatigued or weary).
'world'+'weariness'='WORLD-WEARINESS'

'to' is the link.

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

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