Where does “墨脫” come from?

墨脫 (Chinese) comes from Tibetan མེ་ཏོག, from Tibetan མེན་ཏོག.

Ancestry of “墨脫”, step by step

Step	Language	Word	Meaning
1	Tibetan	མེ་ཏོག	flower, blossom; smallpox
2	Tibetan	མེན་ཏོག	—