rectitude [rek-ti-tood, -tyood]
1 Morally correct behaviour or thinking; moral uprightness, righteousness.
2 The quality or condition of being correct in judgment.
3 The quality of being straight.
As his assistant Ventura (Juan Minujín) starts behaving more like a rival and his landlord’s virtuous daughters sneak men into their bedrooms, Zama’s mask of rectitude slips and with it his grasp on reality. (Ty Burr, 'Zama' is Lucrecia Martel’s latest one-of-a-kind offering, Boston Globe, 2018)
Yet Portugal under António Costa has proved a model of fiscal rectitude, while making tough decisions to clean up the banking system. (Simon Nixon, Portuguese Lessons for Spain and Italy, The Wall Street Journal, 2019)
Her disappointment in Charlotte made her turn with fonder regard to her sister, of whose rectitude and delicacy she was sure her opinion could never be shaken, and for whose happiness she grew daily more anxious, as Bingley had now been gone a week and nothing more was heard of his return. (Jane Austen, Pride and Prejudice)
What object have I, here and now, and everywhere and always, next to the rectitude of my own soul? (David Christie Murray, The Romance of Giovanni Calvotti)
Rectitude has a righteous derivation. It comes straight from the Latin noun rectus, which means both 'right' and 'straight.' 'Rectitude' itself can mean either 'straightness' (an early use referred to literal straightness of lines, although this sense is now rare) or 'rightness' of character. 'Rectus' has a number of other descendants in English, including 'rectangle' (a figure with four right angles), 'rectify' ('to make right'), 'rectilinear' ('moving in or forming a straight line'), and even 'rectus' itself (a medical term for any one of several straight muscles in the body). (MerriamWebster)
early 15c, 'quality of being straight,' from Middle French rectitude (14c.), from Late Latin rectitudinem (nominative rectitudo) 'straightness, uprightness,' from Latin rectus 'straight' (from PIE root *reg- 'move in a straight line,' with derivatives meaning 'to direct in a straight line'). Sense of 'upright in conduct or character' is from 1530s. (Online Etymological Dictionary)