The word "倒霉" is formed through a vivid conceptual metaphor rooted in physical experience. It literally combines "倒" (dǎo), meaning to fall or collapse, with "霉" (méi), meaning mold or mildew. The image conjured is that of something turning moldy and then toppling over, a concrete representation of decay and failure. This visual metaphor was then extended abstractly to describe a person's fortune "going bad" or "rotting", thus semantically evolving to mean having bad luck or being unfortunate.