BEFOUL
foul, befoul, defile, maculate
(verb) spot, stain, or pollute; “The townspeople defiled the river by emptying raw sewage into it”
Source: WordNet® 3.1
Etymology
Verb
befoul (third-person singular simple present befouls, present participle befouling, simple past and past participle befouled)
To make foul; to soil; to contaminate, pollute.
(specifically) To defecate on, to soil with excrement.
(figuratively) To stain or mar (for example with infamy or disgrace).
To entangle or run against so as to impede motion.
Synonyms
• (stain or mar): besmirch, sully, tarnish
Source: Wiktionary
Be*foul", v. t. [imp. & p. p. Befouled; p. pr. & vb. n. Befouling.]
Etym: [Cf. AS. bef; pref. be- + f to foul. See Foul, a.]
1. To make foul; to soil.
2. To entangle or run against so as to impede motion.
Source: Webster’s Unabridged Dictionary 1913 Edition