truthfulness vs honesty

truthfulness and honesty both are nouns.

Word	Noun	Adjective	Verb	Adverb
truthfulness	Yes	No	No	No
honesty	Yes	No	No	No

As nouns, honesty is a hypernym of truthfulness; that is, honesty is a word with a broader meaning than truthfulness:

Other hypernyms of truthfulness include honestness.

truthfulness (noun)	honesty (noun)
the quality of being truthful	the quality of being honest
	southeastern European plant cultivated for its fragrant purplish flowers and round flat papery silver-white seedpods that are used for indoor decoration