objective vs existent

objective is a noun but existent is not a noun.

Word	Noun	Adjective	Verb	Adverb
objective	Yes	Yes	No	No
existent	No	Yes	No	No

objective (noun)	existent (noun)
the lens or system of lenses in a telescope or microscope that is nearest the object being viewed
the goal intended to be attained (and which is believed to be attainable)

objective (adjective)	existent (adjective)
undistorted by emotion or personal bias; based on observable phenomena	having existence or being or actuality
serving as or indicating the object of a verb or of certain prepositions and used for certain other purposes	being or occurring in fact or actuality; having verified existence; not illusory
belonging to immediate experience of actual things or events	presently existing in fact and not merely potential or possible
emphasizing or expressing things as perceived without distortion of personal feelings or interpretation