What Old English word helped inspire J.R.R. Tolkien’s term “Middle-earth”?

The Old English word that helped inspire J.R.R. Tolkien’s term “Middle-earth” is middangeard.

Tolkien’s Middle-earth is connected to the Old English word middangeard, which referred to the inhabited world or human realm. The related Old Norse term miðgarðr and the modern English expression “Middle-earth” also belong to a wider Germanic and mythological tradition describing the world between higher and lower realms.

Tolkien was a philologist whose professional work included the study of Old English and other Germanic languages. He did not invent the expression from nothing, nor did he use it simply as a synonym for the entire planet in every context. In his mythology, Middle-earth is the central region where many events of the Hobbit and the Lord of the Rings take place.

Beowulf is an Old English poem that Tolkien studied and translated, but it is not the word’s source. Heorot is a hall in Beowulf, while wyrd is an Old English concept associated with fate.