Quenya is the fictional language J.R.R. Tolkien developed partly from Finnish for his legendarium.
Tolkien was a professional philologist, and his invented languages were central to the creation of Middle-earth. Quenya belongs to the Elvish language family and was especially associated with the High Elves, including the Ñoldor. Its sound and structure were influenced by Finnish, Latin, and Greek, among other languages Tolkien studied or admired.
Quenya is not simply another name for all Elvish speech in Tolkien’s writings. Sindarin is a different Elvish language, more widely spoken in much of Middle-earth during the events of The Lord of the Rings. Tolkien created grammar, vocabulary, historical changes, and relationships between his languages, treating them as evolving linguistic systems. Because much of the material was published after his death, the surviving evidence is extensive but incomplete, and some forms changed across different stages of his work.