Madhesh (Hindi: मधेश) (Nepali: मधेश) is an Apabhramsha of "Madhyadesh" (Hindi: मध्यदेश) (Nepali: मधेश) used popularly in Nepal interchangeably for its Terai region. The words "Madhesh/Madhyadesh" and the demonyms "Madhyadeshi/Madhesh/Madhesiya" however have more archaic usage in India compared to Nepal. "Madhesh" as an ethnic region within Nepal is sub-divided as "भित्री मधेश" or "Inner Madhesh" and "बाहिरी मधेश" or "Outer Madhesh". The geographical term focuses on the Indo-Gangetic plain's extension into Nepal up to the first Sivalik or Churia foothills, madhesh focuses on the region's population that is racially, culturally and linguistically akin to the population on the Indian side of the border called Madheshi/Madhesiya/Mahadhesi or Deshwaali. The words and their connotations are highly contested by the proponents of the identity and their opponents.
Madhesh excludes the Middle Hills and their populations of Paharis and others.
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