The Lhammas is the name of a work of fiction of etymological subject by J.R.R. Tolkien. It was published in The Lost Road and Other Writings, volume V of The History of Middle-earth. The Lhammas represents an old linguistic view of the Languages of Middle-earth which was later dropped, in which all languages belonged to either the Valarin, Oromëan, Aulëan, or Melkian phylums:
- The Valarin phylum is the origin of all other phylums and led to Valarin (the language of the Valar.)
- Oromëan is named after the Vala Oromë and is used for all languages of the Elves, because Oromë taught the Elves language. Most languages of Men also belong to this phylum.
- Aulëan is named after the Vala Aulë, father of the Dwarves, and is the origin of the Khuzdul language. It has had some influences on the tongues of Men.
- Melkian is named after the fallen Vala Melkor (or Morgoth) and is the origin of the Black Speech of the Orcs and other evil beings.
This entire etymology was dropped as Tolkien further revised the linguistic history of his world, and cannot be applied to the later languages of Middle-earth. However, Tolkien in later writings still held that Rúmil wrote Lammas, but himself never wrote an "updated" form that would be coherent with his later mythology.