Definition of "protectress"

But consider, whether in the sacred promise to be not only a protectress, but a mother to this poor child, your purpose may meet the wishes of the noble knight your husband.

1820, [Walter Scott], chapter I, in The Abbot. […], volume I, Edinburgh: […] [James Ballantyne & Co.] for Longman, Hurst, Rees, Orme, and Brown, […]; and for Archibald Constable and Company, and John Ballantyne, […], page 25

She left a daughter, who was adopted by Lady Evelyn, to share a like fate with her mother; for when I saw Lucy Aylmer, her protectress was dead, and she had returned to her father's house, with a pale cheek and languid step, which showed how little her heart was there.

1834, L[etitia] E[lizabeth] L[andon], chapter XII, in Francesca Carrara. […], volume II, London: Richard Bentley, […], (successor to Henry Colburn), page 123

Her protectress, at this, was upon her again [...]. For the rest of the conversation she was enclosed in Mrs. Wix's arms [...].

1897, Henry James, What Maisie Knew

In Titian’s hands, Diana, protectress of pubescent girls, became a sporty archer in tie-up sandals and bracelets, hair gathered in a loose bun, a silky tunic gaping to reveal one breast, shooting an arrow at her hunky voyeur, who has newly furry ears and a shiny nose, dogs nipping at his crotch.

2007 March 11, Michael Kimmelman, “The Goal Standard”, in New York Times‎