A 17th century Icelandic manuscript depicts a squirrel with an unexplained horn or tusk. This image offers no explanation for the creature's name yet preserves its visual identity. Scholars have long argued over what Ratatoskr actually means in Old Norse. The name contains two elements: rata- and -toskr. Guðbrandur Vigfússon theorized that rati- means "the traveller". He suggested the legendary drill Rati might feature the same term. His theory proposed the full name meant "tusk the traveller" or "the climber tusk." Sophus Bugge offered a different path decades later. He claimed the name was a loanword from Old English meaning "Rat-tooth." Bugge based this on the fact that -toskr appears nowhere else in Old Norse texts. He argued the element came from Old Frisian tusk combined with Old English ræt. Albert Sturtevant challenged Bugge's hypothesis directly. He noted the word Rata appears in Hávamál to signify Odin's boring instrument. Sturtevant concluded Rati must be a native Old Norse word meaning "The Borer, Gnawer." Modern scholars generally accept the "drill-tooth" interpretation instead of the rat-based one.
Primary Mythological Attestations
The Poetic Edda poem Grímnismál describes the squirrel running up and down Yggdrasil. Odin disguised as Grímnir speaks these lines about the creature. The text states Ratatoskr runs at the ash tree to carry words between an eagle and Níðhöggr. Benjamin Thorpe translated the verse as describing how he carries the eagle's words from above. Henry Adams Bellows rendered it as telling them to Nithhogg beneath. These translations preserve the core action of moving messages between opposing forces. The Prose Eddas Gylfaginning chapter 16 provides another account written by Snorri Sturluson. High states that an eagle sits at the top of the ash tree. Between its eyes sits a hawk called Vedrfolnir. The squirrel named Ratatosk runs up and down the ash. He tells slanderous gossip provoking both the eagle and Nidhogg. This description adds a layer of malice to the creature's function beyond simple message delivery. The texts establish the creature exists within the cosmology of Norse mythology.Symbolic Interpretations Of The World Tree
Rudolf Simek suggests the squirrel probably only represents an embellishing detail to the mythological picture. Hilda Ellis Davidson describes the world tree as being gnawed furthering a cycle of destruction and re-growth. She posits the tree symbolizes ever-changing existence through this constant wear. John Lindow points out Yggdrasil is described as rotting on one side. Four harts and Níðhöggr chew on the roots while verbal hostility fills the fauna it supports. Lindow notes that in sagas people who stir up feuds are seldom of high status. This may explain why the role was assigned to a relatively insignificant animal. Richard W. Thorington Jr. and Katie Ferrell theorize the role derived from European tree squirrels giving alarm calls. They suggest the squirrel is saying nasty things about you when danger approaches. These interpretations view the creature not just as a messenger but as a symbol of natural cycles or social discord.