Snotra is the goddess of wisdom, virtue and modesty in Norse mythology. She is considered wise and delicate. Virtuous people find protection in her.
Andy Orchard and Rudolf Simek claim that Snotra, since she appears only in the Prose Edda, is an invention of Snorri. Orchard, however, further argues that Snorri had access to lost sources and that the little information about her was derived from the meaning of her name.
Simek, on the other hand, postulates that Snorri invented Snotra and derived her from the Old Norse word snotr ("wise") and placed her alongside important deities. Perhaps the goddesses Snotra, Saga, Hlín, Sjöfn, Var - according to Simek - are female tutelary goddesses who were worshipped for certain tasks in the private sphere.
One possible explanation is that Snotra was originally an alternative name for another goddess, probably Frigg, and taken by Snorri as a different goddess.
Having nothing else, Snorri informs his readers that Snotra is "wise and graceful" based simply on her name.
It is also conceivable that Snorri had access to an authentic, though scarce, oral tradition that has not been passed down to us from any other source.