/nah day"nee, nah'day nay"/ , n.
1. a group of North American Indian languages, comprising the Athabaskan family, Eyak, Tlingit, and Haida, hypothetically considered to be descendants of a single protolanguage: the genetic relationship of either Tlingit or Haida to Athabaskan and Eyak is now disputed.
2. the hypothesized protolanguage itself.
adj.
3. of, belonging to, or pertaining to Na-Dene.
Also, Nadene .
[ 1915; name coined by Edward Sapir from assumed reflexes of a single Na-Dene root: Haida na to live, house, Tlingit na people, Athabaskan * -ne in dene, repr. a word in Athabaskan languages for "person, people," e.g., Navajo diné ]