The quality or state of being devout; sincere religious belief, dedication, and reverence.
From 'devout' plus '-ness' suffix forming abstract nouns. 'Devout' traces through Old French 'devot' back to Latin 'devotus' (dedicated), ultimately from 'devovere' (to vow).
In Shakespeare and early modern English, 'devoutness' was a supreme virtue—it appears constantly in religious and secular literature as the pinnacle of character quality, but in modern writing it's almost entirely replaced by 'piety' or 'devotion'.
Complete word intelligence in one call. Free tier — 50 lookups/day.