infirm vs weakly

infirm and weakly both are adjectives.

Word	Noun	Adjective	Verb	Adverb
infirm	No	Yes	No	No
weakly	No	Yes	No	Yes

As adjectives, infirm and weakly are synonyms defined as:

Other synonyms of infirm include debile, decrepit, feeble, rickety, sapless, weak.

infirm (adjective)	weakly (adjective)
lacking bodily or muscular strength or vitality	lacking bodily or muscular strength or vitality
lacking firmness of will or character or purpose

infirm (adverb)	weakly (adverb)
	in a weak or feeble manner or to a minor degree