frailty vs cachexia

frailty and cachexia both are nouns.

Word	Noun	Adjective	Verb	Adverb
frailty	Yes	No	No	No
cachexia	Yes	No	No	No

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

frailty: the state of being weak in health or body (especially from old age)
cachexia: any general reduction in vitality and strength of body and mind resulting from a debilitating chronic disease

Other hyponyms of frailty include asthenia, astheny, cachexy, wasting, sickliness.

frailty (noun)	cachexia (noun)
moral weakness	any general reduction in vitality and strength of body and mind resulting from a debilitating chronic disease
the state of being weak in health or body (especially from old age)