The Lhammas (/ˈɬɑmɑs/), Noldorin for "account of tongues", is a work of fictional sociolinguistics, written by J. R. R. Tolkien in 1937, and published in the 1987 The Lost Road and Other Writings, volume five of The History of Middle-earth series.
Tolkien, a philologist, became fascinated by constructed languages, and invented stories to provide his languages with a suitable world, Middle-earth. This resulted in The Lord of the Rings and The Silmarillion. He peopled Middle-earth with Elves and other races, and in the Lhammas presented the theory that all Middle-earth's languages had a shared origin. In the document, he diagrammed the resulting "Tree of Tongues" and described the fictional history of the evolution of some 30 Elvish languages.
Scholars have noted the realism of Tolkien's family of Elvish languages, analogous to the Indo-European family, as well as his changing views of their linguistic history, which he shifted radically soon after creating the Lhammas. The result was that the Noldorin language described in the document and in the contemporaneous The Etymologies, soon became the Sindarin found in The Lord of the Rings, while the new Noldorin became just a dialect of Quenya; Tolkien redrew his "Tree of Tongues" accordingly.