Grace is drawn directly from the English word, itself rooted in Latin gratia, and is commonly linked with both physical elegance and a sense of favor freely given rather than earned. The name is often read as suggesting ease under pressure -- composure that looks effortless, even when it isn't.
Superiour Planets because they most resist, they do not easily receive a detriment or assistance from the Inferiour Planets. - William Lilly (1602.-1681.)