Khuzdul was the language of the Dwarves, invented by Aulë, who taught it to them at their first awakening.

It was a secret tongue of lore, and few who were not Dwarves ever learned it.

Khuzdul seems to have been a rather harsh tongue, with an emphasis on aspirated stops and voiced spirants, but it in no doubt assumed some grace when properly spoken.

The only examples of Khuzdul given are a few personal and place-names, the Dwarves' battle-cry, and the inscription on the tomb of Balin.