J.R.R. Tolkien created Adûnaic as a fictional language for the people of Númenor.
Adûnaic, also spelled Adûnaic or Adunaic in different presentations, was the language of the Númenóreans in Tolkien’s legendarium. It belongs to the language history of Men rather than the Elvish branches represented by Quenya and Sindarin.
Tolkien developed material for Adûnaic while working on the mythology later associated with The Silmarillion and related writings. The language is especially connected with the Númenórean kingdom and its descendants, including the people who later established realms in Middle-earth.
Readers sometimes confuse Adûnaic with Quenya or Sindarin because all three are invented languages in Tolkien’s world. Quenya and Sindarin are Elvish languages, while Adûnaic represents the speech of Númenor’s Men and reflects a different fictional linguistic ancestry.