ham vs ham it up

ham is a noun but ham it up is not a noun.

Word	Noun	Adjective	Verb	Adverb
ham	Yes	No	Yes	No
ham it up	No	No	Yes	No

As verbs, ham and ham it up are synonyms defined as:

Other synonyms of ham include overact, overplay.

ham (noun)	ham it up (noun)
meat cut from the thigh of a hog (usually smoked)
an unskilled actor who overacts
a licensed amateur radio operator

ham (verb)	ham it up (verb)
exaggerate one's acting	exaggerate one's acting