low-spiritedness vs sadness

low-spiritedness and sadness both are nouns.

Word	Noun	Adjective	Verb	Adverb
low-spiritedness	Yes	No	No	No
sadness	Yes	No	No	No

As nouns, sadness is a hypernym of low-spiritedness; that is, sadness is a word with a broader meaning than low-spiritedness:

Other hypernyms of low-spiritedness include unhappiness.

low-spiritedness (noun)	sadness (noun)
a feeling of low spirits	the quality of excessive mournfulness and uncheerfulness
	emotions experienced when not in a state of well-being
	the state of being sad