forcefulness vs vigour

forcefulness and vigour both are nouns.

Word	Noun	Adjective	Verb	Adverb
forcefulness	Yes	No	No	No
vigour	Yes	No	No	No

As nouns, vigour is a hyponym of forcefulness; that is, vigour is a word with a more specific, narrower meaning than forcefulness:

Other hyponyms of forcefulness include brunt, impulse, momentum, energy, vigor, zip.

forcefulness (noun)	vigour (noun)
physical energy or intensity	active strength of body or mind
	an imaginative lively style (especially style of writing)
	forceful exertion