rate vs sluggishness

rate and sluggishness both are nouns.

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

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

rate (noun)	sluggishness (noun)
the relative speed of progress or change	inactivity; showing an unusual lack of energy
amount of a charge or payment relative to some basis	the pace of things that move relatively slowly
a quantity or amount or measure considered as a proportion of another quantity or amount or measure	a state of comatose torpor (as found in sleeping sickness)
a magnitude or frequency relative to a time unit

rate (verb)	sluggishness (verb)
assign a rank or rating to
estimate the value of
be worthy of or have a certain rating