Where does “tirsdag” come from?
tirsdag (Norwegian Bokmål) comes from Danish tirsdag, from Old Norse týsdagr, from Proto-Germanic *Tīwas dag, from Latin dīēs Martis, from Latin diēs, from Proto-Italic djēm, from Proto-Italic *djous, from Proto-Indo-European dyḗws — to be bright; sky, heaven.
tirsdag (Norwegian Bokmål): Tuesday
Ancestry of “tirsdag”, step by step