One of the most incredible parts of The Lord of the Rings, or indeed any of the works of J. R. R. Tolkien, is the depth and vibrancy of the languages he created. This is heavily due to the fact that, even before he first conceived of a Hobbit, Tolkien was a philologist — a scholar of languages. Tolkien’s literary legacy is expansive, covering not only The Lord of the Rings, The Hobbit, and The Silmarillion, but massive amounts of notes and unfinished stories. His son Christopher Tolkien made curating Lord of the Rings‘ secondary material into his life’s work.

https://screenrant.com/lotr-every-language-tolkien-invented-explained/