paper tiger vs impotence

paper tiger and impotence both are nouns.

Word	Noun	Adjective	Verb	Adverb
paper tiger	Yes	No	No	No
impotence	Yes	No	No	No

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

paper tiger: the nature of a person or organization that appears powerful but is actually powerless and ineffectual
impotence: the quality of lacking strength or power; being weak and feeble

Other hypernyms of paper tiger include impotency, powerlessness.

paper tiger (noun)	impotence (noun)
the nature of a person or organization that appears powerful but is actually powerless and ineffectual	the quality of lacking strength or power; being weak and feeble
	an inability (usually of the male animal) to copulate