It's meaningless for those without nous (7,5)

I believe the answer is:

lacking sense

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'it's meaningless for those' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'without nous' is the wordplay.
'without' becomes 'lacking' (I've seen this in another clue).
'nous' becomes 'sense' (I've seen this before).
'lacking'+'sense'='LACKING SENSE'

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