uncheerfulness vs attribute

uncheerfulness and attribute both are nouns.

Word	Noun	Adjective	Verb	Adverb
uncheerfulness	Yes	No	No	No
attribute	Yes	No	Yes	No

As nouns, attribute is a hypernym of uncheerfulness; that is, attribute is a word with a broader meaning than uncheerfulness:

uncheerfulness (noun)	attribute (noun)
not conducive to cheer or good spirits	an abstraction belonging to or characteristic of an entity
a feeling of dreary or pessimistic sadness	a construct whereby objects or individuals can be distinguished

uncheerfulness (verb)	attribute (verb)
	attribute or credit to
	decide as to where something belongs in a scheme