centrism vs ideology

centrism and ideology both are nouns.

Word	Noun	Adjective	Verb	Adverb
centrism	Yes	No	No	No
ideology	Yes	No	No	No

As nouns, ideology is a hypernym of centrism; that is, ideology is a word with a broader meaning than centrism:

centrism: a political philosophy of avoiding the extremes of left and right by taking a moderate position or course of action
ideology: an orientation that characterizes the thinking of a group or nation

Other hypernyms of centrism include political orientation, political theory.

centrism (noun)	ideology (noun)
a political philosophy of avoiding the extremes of left and right by taking a moderate position or course of action	an orientation that characterizes the thinking of a group or nation
	imaginary or visionary theorization