- a group of North American Indian languages, comprising the Athabascan family, Eyak, Tlingit, and Haida, hypothetically considered to be descendants of a single protolanguage: the genetic relationship of either Tlingit or Haida to Athabascan and Eyak is now disputed.
- the hypothesized protolanguage itself.
- of, belonging to, or pertaining to Na-Dene.
- a phylum of North American Indian languages including Athapascan, Tlingit, and Haida
