Negative. Utter nonsense! (3,4)

I believe the answer is:

not true

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'negative utter nonsense' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'negative utter nonsense' is the wordplay.
'negative' becomes 'no' (no is a kind of negative).
'nonsense' indicates anagramming the letters.
'utter' anagrammed gives 'ttrue'.
'no'+'ttrue'='NOT TRUE'

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