Sentence:  (Muspelheim, we suppose, with its numerous fiery inhabitants, and their mighty chief <WSD>Surtur</WSD>, the dark, the incomprehensible, the great evil principle, had no beginning; or if it had, the Odinian theologians were unacquainted with it.) 
Meaning of the word marked with <WSD> tags:  A very powerful jotun (giant) and chief of Muspellheim, described in the Eddas as wielding a flaming (or shining) sword and as battling the gods and killing Freyr during Ragnarok.