relativistic vs relativity

relativistic is not a noun while relativity is a noun.

Word	Noun	Adjective	Verb	Adverb
relativistic	No	Yes	No	No
relativity	Yes	No	No	No

relativistic (noun)	relativity (noun)
	the quality of being relative and having significance only in relation to something else
	(physics) the theory that space and time are relative concepts rather than absolute concepts

relativistic (adjective)	relativity (adjective)
relating or subject to the special or the general theory of relativity
of or relating to the philosophical doctrine of relativism