Languages of the Dwarves: Khuzdul

Khuzdul is the language taught to the dwarves by their creator the Vala Aulë. While they themselves, of course, speak it expertly, it proves near impossible for strangers to learn. It is rarely spoken among or taught to outsiders. Another reason for difficulties that some might experience when attempting to learn Khuzdul is the fact that much of it is based on triconsonantal roots, something that is not common among the other currently actively spoken languages of Middle Earth. Additionally it consists of 50 letters that to foreigners tend to resemble sounds rather than actual letters.

Its first script, rune letters called Cirth, is said to have been developed by the elven loremaster Daeron of Doriath. However, the dwarves eventually stopped using that script entirely and developed their own runes, called Angerthas, in several stages: Angerthas Moria and Angerthas Erebor. They have also devised a hidden, secret form of runes called Moonletters which can only be seen under the light of the moon during the right time of night or season.