weakness vs impotence

weakness and impotence both are nouns.

Word	Noun	Adjective	Verb	Adverb
weakness	Yes	No	No	No
impotence	Yes	No	No	No

As nouns, impotence is a hypernym of weakness; that is, impotence is a word with a broader meaning than weakness:

Other hypernyms of weakness include impotency, powerlessness.

weakness (noun)	impotence (noun)
the property of lacking physical or mental strength; liability to failure under pressure or stress or strain	the quality of lacking strength or power; being weak and feeble
powerlessness revealed by an inability to act	an inability (usually of the male animal) to copulate
a penchant for something even though it might not be good for you
a flaw or weak point
the condition of being financially weak