The word hillbilly refers to a negative stereotype of people from Appalachia. The term hillbilly is considered to be a modern term because it showed up in the early 1900s. Though the word is Scottish in origin, but doesn't derive from dialect.
In the context of a negative stereotype, people from Appalachia are often referred to as "hillbillies," a term that originated in the early 1900s. Although the word has Scottish origins, it is not derived from local dialect.