subdialects

/ˌsʌbˈdaɪəˌlɛkts/
noun
  1. A smaller, more specific variety of a dialect, spoken in a particular area or by a particular group within a larger dialect region.
    • Within the broader New York City dialect, there are subdialects spoken in Brooklyn, Queens, and Staten Island.
    • The linguist studied the subdialects of the Appalachian region, noting differences in vocabulary from one valley to the next.
    • Older residents often use subdialects that younger people in the same town no longer recognize.