muck up vs spoil

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

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

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

muck up (noun)	spoil (noun)
	the act of stripping and taking by force
	the act of spoiling something by causing damage to it
	(usually plural) valuables taken by violence (especially in war)

muck up (verb)	spoil (verb)
soil with mud, muck, or mire	become unfit for consumption or use
make a mess of, destroy or ruin	alter from the original
	make imperfect
	destroy and strip of its possession
	have a strong desire or urge to do something
	hinder or prevent (the efforts, plans, or desires) of
	treat with excessive indulgence
	make a mess of, destroy or ruin