rectitude vs uprightness

rectitude and uprightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
rectitude	Yes	No	No	No
uprightness	Yes	No	No	No

As nouns, rectitude and uprightness are synonyms defined as:

rectitude and uprightness: righteousness as a consequence of being honorable and honest

rectitude (noun)	uprightness (noun)
righteousness as a consequence of being honorable and honest	righteousness as a consequence of being honorable and honest
	position at right angles to the horizon
	the property of being upright in posture