The Nakai language is a language spoken by the Nakai that sounds like clicks and screeches to human. They have a written language that consists out of various picture symbols.
The Nakai communicated in their native language with the Destiny expedition, although it was automatically translated into English by the Destiny AI and vice versa.(SGU: "Space", "Divided")
In 2009, Chloe Armstrong, with the Nakai pathogen, understood the language when she, Eli Wallace, Matthew Scott were in a Nakai fighter on the Gravel pit planet. (SGU: "Lost")