obnubilate

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 andobnubilate 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

Obnubilate, a late 16th century word, is a verbal derivative of the Latin nūbilus meaning "cloudy," though its closer ancestor, obnūbilāre means "to darken."