asthenia vs frailness

asthenia and frailness both are nouns.

Word	Noun	Adjective	Verb	Adverb
asthenia	Yes	No	No	No
frailness	Yes	No	No	No

As nouns, frailness is a hypernym of asthenia; that is, frailness is a word with a broader meaning than asthenia:

asthenia: an abnormal loss of strength
frailness: the state of being weak in health or body (especially from old age)

Other hypernyms of asthenia include debility, feebleness, frailty, infirmity, valetudinarianism.

asthenia (noun)	frailness (noun)
an abnormal loss of strength	the state of being weak in health or body (especially from old age)