ob ‧ tuse /əbˈtjuːs $ -ˈtuːs/ BrE AmE adjective formal
[ Date: 1500-1600 ; Language: Latin ; Origin: obtusus 'blunt' , from obtundere 'to beat against, make blunt' ]
slow to understand things, in a way that is annoying:
‘But why?’ said Charles, being deliberately obtuse.
—obtuseness noun [uncountable]