The form dor in the Etymologies is a misreading, see VT/45. In composition and in toponyms, the word is nevertheless reduced to Dor
Noldorin
doriath
place name. Land of the Cave
ardholen
place name. Hidden Realm
dor
noun. land, dwelling-place, region where certain people live
edhel
noun. Elf
golodh
noun. "Deep Elf" or "Gnome", one of the Wise Folk
golodhrim
noun. Deep Elves, Gnomes
A Noldorin equivalent of Ilk. Garthurian “Fenced Realm, Hidden Realm” appearing in The Etymologies from the 1930s (Ety/GAT(H)). It seems to be a combination of ardh “realm” and the lenited form of dolen “hidden”. The related name Arthoren has a different meaning: “Fenced Realm”