§ Of the Sindar The Silmarillion

It came to pass during the second age of the captivity of Melkor that Dwarves came over the Blue Mountains of Ered Luin into Beleriand. Themselves they named Khazâd, but the Sindar called them Naugrim, the Stunted People, and Gonnhirrim, Masters of Stone. Far to the east were the most ancient dwellings of the Naugrim, but they had delved for themselves great halls and mansions, after the manner of their kind, in the eastern side of Ered Luin; and those cities were named in their own tongue Gabilgathol and Tumunzahar. To the north of the great height of Mount Dolmed was Gabilgathol, which the Elves interpreted in their tongue Belegost, that is Mickleburg; and southward was delved Tumunzahar, by the Elves named Nogrod, the Hollowbold. Greatest of all the mansions of the Dwarves was Khazâd-dûm, the Dwarrowdelf, Hadhodrond in the Elvish tongue, that was afterwards in the days of its darkness called Moria; but it was far off in the Mountains of Mist beyond the wide leagues of Eriador, and to the Eldar came but as a name and a rumour from the words of the Dwarves of the Blue Mountains.