Neurotic's blunder is stupid (9)

I believe the answer is:

cretinous

'is stupid' is the definition.
(I've seen this before)

'neurotic's blunder' is the wordplay.
'blunder' indicates anagramming the letters.
'neurotics' is an anagram of 'CRETINOUS'.

(Another definition for cretinous that I've seen is " Very stupid".)

I've seen this clue in The Daily Express.

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