Superior reason not to be buried (11)

I believe the answer is:

aboveground

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'not to be buried' is the definition.
I can't judge whether this defines the answer.

'superior reason' is the wordplay.
'superior' becomes 'above' (I've seen this in another clue).
'reason' becomes 'ground' (synonyms).
'above'+'ground'='ABOVEGROUND'

Can you help me to learn more?

I've seen this clue in The Daily Express.

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