Lairs measure bent character for stupidity (9)

I believe the answer is:

denseness

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'for stupidity' is the definition.
(denseness is a kind of stupidity)

'lairs measure bent character' is the wordplay.
'lairs' becomes 'dens' ('den' can be a synonym of 'lair').
'measure' becomes 'en' (en is a unit of measurement used by printers).
'bent character' becomes 'ess' (the letter S. I am not sure about the 'bent' bit.).
'dens'+'en'+'ess'='DENSENESS'

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(Another definition for denseness that I've seen is " Stupidity".)

I've seen this clue in the Sydney Morning Herald.

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