recrudescence

Recrudescence derives from the Latin verb recrudescere, meaning "to become raw again" (used, for example, of wounds). Ultimately, it can be traced back to the Latin word for raw," which is "crudus." (If you suspect that "crude" is also derived from "crudus," you are correct; another well-known descendant is "cruel.") In its literal sense, "recrudescence" is a medical word denoting a renewed outbreak of a disease. In extended use, it most often describes the return of an undesirable condition, such as a war or a plague, or the return of an undesirable idea.