frailness vs debility

frailness and debility both are nouns.

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

As nouns, frailness and debility are synonyms defined as:

frailness and debility: the state of being weak in health or body (especially from old age)

Other synonyms of frailness include feebleness, frailty, infirmity, valetudinarianism.

frailness (noun)	debility (noun)
the state of being weak in health or body (especially from old age)	the state of being weak in health or body (especially from old age)