vis inertiae
Latin, “force of inactivity.” Lady Lufton disapproves of Lucy for being too passionate and active; she believes that beauty is to be found in restraint and reticence. Perhaps Trollope uses Latin as a reminder of Griselda (Lady Lufton’s favorite prospect for her son’s marriage), who with her passivity and coldness is reminiscent of a Classical statue. See the commentary for Chapter 11. [JM 2005]