late 14c., "of or belonging to home or household, domestic," from Middle English hom "home" (see home, n.) + -ly(2). Sense of "plain, unadorned, simple" is late 14c., and extension to "having a plain appearance, ugly, crude" took place c.1400, but now survives chiefly in U.S., especially in New England, where it was the usual term for "physically unattractive;" ugly being typically "ill-tempered."