Thursday

Thursday comes from Middle English Thuresday, from Old English þursdæġ or þunresdæġ, literally 'Thor's day,' possibly influenced by Old Norse þórsdagr — both tracing back to Proto-West Germanic *Þunras dag, 'day of the thunder god.'

The name likely began as a straightforward tribute to Thor, the thunder god, and may have been reshaped through contact with Norse speakers who used their own version, þórsdagr, for the same day.

It's a calque of Latin diēs Iovis ('day of Jove'), since early Germanic peoples matched their thunder god Thor with the Roman thunder god Jupiter when naming the days of the week.