In the Poetic Edda poem Alvíssmál, Thor tricks the dwarf Alvíss until sunrise. Alvíss arrives expecting to marry Thor’s daughter, who is not named in the poem.
Thor says he will not approve the marriage until Alvíss answers questions about the names used by different groups for natural and cosmic things. The dwarf responds with a series of poetic synonyms, including terms used by gods, giants, elves, dwarves, humans, and the dead.
The questioning continues until daylight. Because dwarves turn to stone when exposed to sunlight in this literary tradition, Alvíss is defeated without Thor needing to fight him directly. The poem ends by revealing that Thor has outwitted his unwelcome guest.
Alvíssmál is preserved in the Codex Regius manuscript of the Poetic Edda. Its catalogue of alternate names also makes it valuable evidence for medieval Norse poetic vocabulary.