Herb of Grace.

Rue is so called because of its use in exorcism, and hence the Roman Catholics sprinkle holy water with a bunch of rue. It was for centuries supposed to prevent contagion. Rue is the German raute; Greek, rutē; Latin, ruta, meaning the “preserver,” being a preservative of health (Greek, ruo, to preserve). Ophelia calls it the “Herb of Grace oʹ Sundays.”