befoul vs defile

befoul is not a noun while defile is a noun.

Word	Noun	Adjective	Verb	Adverb
befoul	No	No	Yes	No
defile	Yes	No	Yes	No

As verbs, befoul and defile are synonyms defined as:

Other synonyms of befoul include foul, maculate.

befoul (noun)	defile (noun)
	a narrow pass (especially one between mountains)

befoul (verb)	defile (verb)
spot, stain, or pollute	spot, stain, or pollute
	make dirty or spotty, as by exposure to air; also used metaphorically
	place under suspicion or cast doubt upon