Definitions

1. verb

to make or become foul or filthy

“The river began to befilth the nearby lake with its pollutants.”

2. noun

a state of being foul or filthy

“The befilth of the city streets was a major concern for the local government.”

3. verb (archaic or poetic)

to cover or stain with filth or foul matter

“The dark clouds began to befilth the landscape with their ominous presence.”