furthermost vs comparative

furthermost is not a noun while comparative is a noun.

Word	Noun	Adjective	Verb	Adverb
furthermost	No	Yes	No	No
comparative	Yes	Yes	No	No

furthermost (noun)	comparative (noun)
	the comparative form of an adjective or adverb

furthermost (adjective)	comparative (adjective)
(comparatives of `far') most remote in space or time or order	estimated by comparison; not absolute or complete
	relating to or based on or involving comparison