gravity vs graveness

gravity and graveness both are nouns.

Word	Noun	Adjective	Verb	Adverb
gravity	Yes	No	No	No
graveness	Yes	No	No	No

As nouns, gravity and graveness are synonyms defined as:

Other synonyms of gravity include soberness, sobriety, somberness, sombreness.

gravity (noun)	graveness (noun)
a manner that is serious and solemn	a manner that is serious and solemn
a solemn and dignified feeling
(physics) the force of attraction between all masses in the universe; especially the attraction of the earth's mass for bodies near its surface