possible vs viable

possible is a noun but viable is not a noun.

Word	Noun	Adjective	Verb	Adverb
possible	Yes	Yes	No	No
viable	No	Yes	No	No

possible (noun)	viable (noun)
something that can be done
an applicant who might be suitable

possible (adjective)	viable (adjective)
capable of happening or existing	capable of life or normal growth and development
existing in possibility	capable of being done with means at hand and circumstances as they are