last word vs rakishness

last word and rakishness both are nouns.

Word	Noun	Adjective	Verb	Adverb
last word	Yes	No	No	No
rakishness	Yes	No	No	No

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

Other hyponyms of last word include dapperness, jauntiness, nattiness.

last word (noun)	rakishness (noun)
elegance by virtue of being fashionable	stylishness as evidenced by a smart appearance
the final statement in a verbal argument	the quality of a rake
an authoritative statement