Subdialect

Subdialect (from Latin sub-, "under", and Ancient Greek διάλεκτος, diálektos, "discourse") is a linguistic term designating a dialectological category between the levels of dialect and idiolect. Subdialects are basic subdivisions of a dialect. Subdialects can be divided further, ultimately down to idiolects. Subdialects of one dialect are generally quite close to each other, differing mainly in pronunciation and certain local words.