sourness

From Middle English sowrenesse, sournesse, from Old English sūrnes (“sourness”), equivalent to sour +‎ -ness.

sourness (countable and uncountable, plural sournesses)

1. The quality or condition of being sour, usually said of human personalities.
   • 1811, Jane Austen, chapter 2.1, in Sense and Sensibility:

     Mrs. Ferrars was a little, thin woman, upright, even to formality, in her figure, and serious, even to sourness, in her aspect.

• sunroses