oddness vs eccentricity

oddness and eccentricity both are nouns.

Word	Noun	Adjective	Verb	Adverb
oddness	Yes	No	No	No
eccentricity	Yes	No	No	No

As nouns, eccentricity is a hypernym of oddness; that is, eccentricity is a word with a broader meaning than oddness:

oddness (noun)	eccentricity (noun)
eccentricity that is not easily explained	strange and unconventional behavior
the parity of odd numbers (not divisible by two)	a circularity that has a different center or deviates from a circular path
	(geometry) a ratio describing the shape of a conic section; the ratio of the distance between the foci to the length of the major axis