governor vs politician

governor and politician both are nouns.

Word	Noun	Adjective	Verb	Adverb
governor	Yes	No	No	No
politician	Yes	No	No	No

As nouns, politician is a hypernym of governor; that is, politician is a word with a broader meaning than governor:

governor (noun)	politician (noun)
a control that maintains a steady speed in a machine (as by controlling the supply of fuel)	a person active in party politics
the head of a state government	a leader engaged in civil administration
	a schemer who tries to gain advantage in an organization in sly or underhanded ways