relativity vs relative

relativity and relative both are nouns.

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

relativity (noun)	relative (noun)
the quality of being relative and having significance only in relation to something else	an animal or plant that bears a relationship to another (as related by common descent or by membership in the same genus)
(physics) the theory that space and time are relative concepts rather than absolute concepts	a person related by blood or marriage

relativity (adjective)	relative (adjective)
	estimated by comparison; not absolute or complete
	properly related in size or degree or other measurable characteristics; usually followed by `to'