obnubilate \ob-NOO-buh-leyt\, verb:
to cloud over; becloud; obscure.
...their trunks were black and knobbly, whilst their branches buckled over as a roof to meet a brick plane and obnubilate a view of the stars.
-- Colin Cornelius, Monkeys Can't Swim
It is the pity of the world, Dr Maturin, to see a man of your parts obnubilate his mind with the juice of the poppy.
-- Patrick O'Brian, The Mauritius Command
Me: This exhaustion is obnubilating my thought processes. I guess another cup of coffee is warranted.