There are several synonyms for the word "chin" including jawline, mandible, jowl, and lower face. The jawline refers to the area where the lower jawbone meets the neck, while the mandible is the technical term for the jaw bone itself. Jowl is a term often used to describe the loose flesh below the jawline, and lower face refers to the entire lower portion of the face, including the chin, jawline and cheeks. While these terms may have slightly different meanings, they are often used interchangeably when referring to the chin or lower face area.