Written by Dyami Millarson
Wilhelm Mannhardt says on page 190 of his work: “Aus diesem Grunde wohnen die Tossar in Grabhügeln.” (For this reason, the Tossar dwell in burial mounds.)
The explanation can be found in what Mannhardt says on page 169 of the same work: “altnord. þurs, norweg. tusse, dän. schwed. tosse.” (Old Nordic þurs, Norwegian tusse, Danish [and] Swedish tosse.)
Mannhardt does, however, not explicitly link the singulars of the aforementioned nouns with their plurals: Tossar is the plural of the Danish/Swedish form Tosse, which is related to Norwegian Tussar (singular Tuss or Tusse). All these cognates ultimately come from Þursar Giants (singular Þurs).
Tosse/Tusse has come to mean simpleton, so it may not readily be understood as Þurs in modern times. It is, nevertheless, worth reviving the old meaning of these Nordic cognates.
Viking Religion 