Quenya is the Tolkien language spoken by the Elves of Valinor in his legendarium.
Quenya is one of Tolkien’s best-developed Elvish languages. He based parts of its sound and structure on languages including Finnish, and he created vocabulary and grammar for it over many years. In the history of Middle-earth, Quenya was associated especially with the Ñoldor and with the Elves who lived in Aman, including Valinor.
Sindarin is another major Elvish language, more widely used in much of Middle-earth during the time of The Lord of the Rings. The two languages are related within Tolkien’s fictional history but are not the same language.
Quenya’s status also changes across the legendarium. In Middle-earth it can function as a formal, ancient, or scholarly language rather than an everyday vernacular. This is why identifying it simply as “the Elvish language” can obscure the distinction between Tolkien’s several constructed languages.