cheating vs two-timing

cheating is a noun but two-timing is not a noun.

Word	Noun	Adjective	Verb	Adverb
cheating	Yes	Yes	No	No
two-timing	No	Yes	No	No

As adjectives, cheating and two-timing are synonyms defined as:

Other synonyms of cheating include adulterous.

cheating (noun)	two-timing (noun)
a deception for profit to yourself

cheating (adjective)	two-timing (adjective)
violating accepted standards or rules	not faithful to a spouse or lover
not faithful to a spouse or lover