What does Ulf mean?
From the Old Norse 'ulfr', meaning 'wolf'. A common standalone name in medieval Scandinavia and the source of the '-ulf' ending in many Norse compound names.
What does Fafnir mean?
Old Norse Fafnir, the dwarf who turned into a dragon guarding a cursed hoard in the Volsung legend. Flag: this is the NAME OF a mythological dragon, not a common word meaning 'dragon'; its own etymology is not securely established, so it qualifies by being a famous dragon-bearer rather than by literal translation.