Jeju language
Jeju (Jeju: 제줏말; Jeju RR: Jejunmal, or Korean: 제주어; RR: Jejueo, or 제주말; Jejumal), often called Jejueo or Jejuan in English-language scholarship, is a Koreanic language originally from Jeju Island, South Korea. It is not mutually intelligible with mainland Korean dialects.