muck up vs mud

muck up is not a noun while mud is a noun.

Word	Noun	Adjective	Verb	Adverb
muck up	No	No	Yes	No
mud	Yes	No	Yes	No

As verbs, muck up and mud are synonyms defined as:

Other synonyms of muck up include mire, muck.

muck up (noun)	mud (noun)
	slanderous remarks or charges
	water soaked soil; soft wet earth

muck up (verb)	mud (verb)
soil with mud, muck, or mire	soil with mud, muck, or mire
make a mess of, destroy or ruin	plaster with mud