Crazy sort of lament (6)

I believe the answer is:

mental

'crazy' is the definition.
(mentally ill)

'sort of lament' is the wordplay.
'sort of' indicates anagramming the letters.
'lament' with letters rearranged gives 'MENTAL'.

(Other definitions for mental that I've seen before include "Cognitive" , "Intellectual" , "Relating to the mind" , "like brain operation" , "Involving the mind" .)

I've seen this clue in The Daily Express.

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