soil vs muddy

soil is a noun but muddy is not a noun.

Word	Noun	Adjective	Verb	Adverb
soil	Yes	No	Yes	No
muddy	No	Yes	Yes	No

As verbs, muddy is a hyponym of soil; that is, muddy is a word with a more specific, narrower meaning than soil:

Other hyponyms of soil include foul, contaminate, foul, pollute, smear, slime, muddy up, splash, mire, muck, muck up, mud, crock, blemish, spot.

soil (noun)	muddy (noun)
the geographical area under the jurisdiction of a sovereign state
material in the top layer of the surface of the earth in which plants can grow (especially with reference to its quality or use)
anything regarded as making something unclean
the part of the earth's surface consisting of humus and disintegrated rock

soil (adjective)	muddy (adjective)
	dirty and messy; covered with mud or muck
	(of color) discolored by impurities; not bright and clear
	(of liquids) clouded as with sediment
	(of soil) soft and watery