"bare, sandy tract by the sea," late 13c., of uncertain origin, perhaps connected to dune, but the sense and the phonology are difficult. Related: Dene-hole (1768) "ancient artificial excavation in the chalk-formations of southern England." By local folk etymology Dane-hole, and reputed to be where the vikings hid their treasure, but there is no historical evidence for this.
in reference to a group of related North American native languages, 1915, coined by U.S. anthropologist and linguist Edward Sapir from *-ne, a stem in the languages for "person, people," and Athabaskan Dene "person, people." "The compound term Na-dene thus designates by means of native stems the speakers of the three languages concerned, besides continuing the use of the old term Dene for the Athabaskan branch of the stock" [Sapir].
c. 1600, "quality of being very close or compact," from French densité (16c.), from Old French dempsité (13c.), from Latin densitas "thickness," from densus "thick, dense" (see dense). In physics, "the mass of matter per unit of bulk," 1660s.
Proto-Indo-European root meaning "tooth."
It forms all or part of: al dente; dandelion; dental; dentifrice; dentist; dentition; denture; glyptodon; indent (v.1) "to make notches;" mastodon; orthodontia; periodontal; teethe; tooth; toothsome; tusk; trident.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit danta, Greek odontos (gen.), Latin dens, Lithuanian dantis, Old Irish det, Welsh dent, Old English toð, German Zahn, Gothic tunþus "tooth."