Khuzdul is a language that was created for the dwarves in J.R.R. Tolkien's books like "The Hobbit" and "The Lord of the Rings". It's a language that the dwarves use to talk to each other and it sounds very different from English. It has lots of hard sounds and is very guttural.
All the words in Khuzdul have their own special meaning and they're often used to describe things that are important to the dwarves like their mines, their weapons and their family. Khuzdul even has its own alphabet with special symbols that dwarves can use to write letters to each other.
But because Khuzdul is a made-up language, not many people know how to speak it. Only the dwarves in Tolkien's books and a few people who are really big fans of those stories know how to speak it. So if you meet someone who speaks Khuzdul, consider yourself lucky because it's a very unique language!