armchair liberal vs liberalist

armchair liberal and liberalist both are nouns.

Word	Noun	Adjective	Verb	Adverb
armchair liberal	Yes	No	No	No
liberalist	Yes	No	No	No

As nouns, liberalist is a hypernym of armchair liberal; that is, liberalist is a word with a broader meaning than armchair liberal:

armchair liberal: a person of liberal ideals who takes no action to realize them
liberalist: a person who favors a political philosophy of progress and reform and the protection of civil liberties

Other hypernyms of armchair liberal include liberal, progressive.

armchair liberal (noun)	liberalist (noun)
a person of liberal ideals who takes no action to realize them	a person who favors a political philosophy of progress and reform and the protection of civil liberties