sluggishness vs torpidity

sluggishness and torpidity both are nouns.

Word	Noun	Adjective	Verb	Adverb
sluggishness	Yes	No	No	No
torpidity	Yes	No	No	No

As nouns, torpidity is a hypernym of sluggishness; that is, torpidity is a word with a broader meaning than sluggishness:

sluggishness: a state of comatose torpor (as found in sleeping sickness)
torpidity: a state of motor and mental inactivity with a partial suspension of sensibility

Other hypernyms of sluggishness include torpor.

sluggishness (noun)	torpidity (noun)
inactivity; showing an unusual lack of energy	inactivity resulting from lethargy and lack of vigor or energy
the pace of things that move relatively slowly	a state of motor and mental inactivity with a partial suspension of sensibility
a state of comatose torpor (as found in sleeping sickness)