dûm
From Tolkien Gateway
dûm means "hall, mansions" and/or "excavations" in Khuzdul.
It is seen in the name Khazad-dûm, the name of Moria
Etymology
It is possible that the actual form of the word is *tumum (root *T-M-M); the form dûm is assimilated (from Khazad-).[1]
References
- ↑ An analysis of Dwarvish by Magnus Åberg; he bases this on the word Tumunzahar
