Nevbosh was the invented language that J.R.R. Tolkien described in his 1931 essay “A Secret Vice.”
Tolkien created Nevbosh with his cousins during childhood. The name is generally explained as “new nonsense,” and the language combined altered elements from English, French and Latin with Tolkien’s own inventions. It was an early example of his lifelong interest in making languages.
In “A Secret Vice,” Tolkien discusses the pleasure of inventing languages and argues that a language can be created for aesthetic reasons rather than only for practical communication. He also mentions other experiments, including Naffarin, an early personal language.
Nevbosh should not be confused with Qenya, an early form of the Elvish language that Tolkien developed later and connected to his mythology. Nevbosh predates the mature linguistic systems associated with Middle-earth.