infirmity vs debility

infirmity and debility both are nouns.

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

As nouns, infirmity and debility are synonyms defined as:

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

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

infirmity (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)