Definition of befouling:
(v) :
(literally) To make foul; to soil; to contaminate, pollute.
(v) :
(specifically) To defecate on, to soil with excrement.
(v) :
(figuratively) To stain or mar (e.g., with infamy or disgrace).
(v) :
(figuratively) To entangle or run against so as to impede motion.