existent vs face of the earth

existent is not a noun while face of the earth is a noun.

Word	Noun	Adjective	Verb	Adverb
existent	No	Yes	No	No
face of the earth	Yes	No	No	No

existent (noun)	face of the earth (noun)
	the state or fact of existing

existent (adjective)	face of the earth (adjective)
having existence or being or actuality
being or occurring in fact or actuality; having verified existence; not illusory
presently existing in fact and not merely potential or possible