geniality vs mellowness

geniality and mellowness both are nouns.

Word	Noun	Adjective	Verb	Adverb
geniality	Yes	No	No	No
mellowness	Yes	No	No	No

As nouns, mellowness is a hyponym of geniality; that is, mellowness is a word with a more specific, narrower meaning than geniality:

Other hyponyms of geniality include condescendingness, condescension, sweetness and light.

geniality (noun)	mellowness (noun)
a disposition to be friendly and approachable (easy to talk to)	the property of a sensation that is rich and pleasing
	a soft shade of a color
	geniality, as through the effects of alcohol or marijuana
	a taste (especially of fruit) that is ripe and of full flavor
	a feeling of good humor and sympathy through maturity or intoxication or a relaxed state