…sooner than that her child should make ignoble the blood which it had cost her so much to ennoble, she would do deeds which should make even the wickedness of her husband child's play in the world's esteem.
-- Anthony Trollope, Lady Anna, 1871
Her small chiselled nose, her mouth so delicately curved, gave token of taste. In the whole was harmony, and the upper part of the countenance seemed to reign over the lower and to ennoble it, making her usual placid expression thoughtful and earnest...
-- Mary Shelley, Lodore, 1833
Ennoble comes from the Latin nobilis meaning "well-known" or "high born," which in turn came from the Proto-Indo-European root gno- meaning "to know."