Sindarin is the fictional Elvish language J.R.R. Tolkien created for the Elves of Beleriand.
Within Tolkien’s mythology, Sindarin developed from an earlier Elvish language and became the everyday language of many Elves in Middle-earth, especially in Beleriand during the First Age. Its sound and structure were influenced strongly by Welsh.
Sindarin is often confused with Quenya, another major Elvish language. Quenya is associated with the High Elves and has influences from Finnish, while Sindarin was intended to have a different sound and historical role. Both languages have internal histories and dialectal variation in Tolkien’s writings.
Tolkien approached his invented languages as philological systems rather than collections of decorative words. He created sound changes, grammar, vocabulary, and relationships between languages, making language development central to the mythology’s design.