killing vs cleanup

killing and cleanup both are nouns.

Word	Noun	Adjective	Verb	Adverb
killing	Yes	Yes	No	No
cleanup	Yes	No	No	No

As nouns, killing and cleanup are synonyms defined as:

killing (noun)	cleanup (noun)
the act of terminating a life	the act of making something clean
an event that causes someone to die	(baseball) the fourth position in the batting order (usually filled by the best batter on the team)
a very large profit	a very large profit

killing (adjective)	cleanup (adjective)
very funny