pollyanna

pollyanna [ˌpɒliˈænə] n.

1.) A person regarded as being foolishly or blindly optimistic (American Heritage Dictionary of the English Language).

Etymology: After the heroine of the novel Pollyanna, by the American writer Eleanor Hodgman Porter (1868-1920).

"Job's crops are destroyed, his barns burned, his children taken sick, and he himself breaks out all over with boils. In this condition he is visited by a group of three friends—professional moralists and Pollyannas—and between them and him the dramatic debate ensues" (The Man and the Book Nobody Knows, Bruce Barton, 1959).

(Job and His Daughters, William Blake, 1800)