imperialism vs ideology

imperialism and ideology both are nouns.

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

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

imperialism: a political orientation that advocates imperial interests
ideology: an orientation that characterizes the thinking of a group or nation

Other hypernyms of imperialism include political orientation, political theory.

imperialism (noun)	ideology (noun)
any instance of aggressive extension of authority	an orientation that characterizes the thinking of a group or nation
a political orientation that advocates imperial interests	imaginary or visionary theorization
a policy of extending your rule over foreign countries