smoothness vs evenness

smoothness and evenness both are nouns.

Word	Noun	Adjective	Verb	Adverb
smoothness	Yes	No	No	No
evenness	Yes	No	No	No

As nouns, evenness is a hypernym of smoothness; that is, evenness is a word with a broader meaning than smoothness:

Other hypernyms of smoothness include invariability.

smoothness (noun)	evenness (noun)
a texture without roughness; smooth to the touch	a quality of uniformity and lack of variation
the quality of having a level and even surface	the quality of being balanced
the quality of being free from errors or interruptions	the parity of even numbers (divisible by two)
the quality of being bland and gracious or ingratiating in manner
powerful and effective language