feebleness vs debility

feebleness and debility both are nouns.

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

As nouns, feebleness and debility are synonyms defined as:

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

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

feebleness (noun)	debility (noun)
the quality of lacking intensity or substance	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)