köken: From Middle High German mōntac, māntac, from Old High German mānotag (9th c.), māntag (12th c.), from Proto-West Germanic *mānini dag (“day of the moon”), equivalent to Mond + Tag. Compare Low German Maandag, Dutch maandag, English Monday, Danish mandag.
köken: Inherited from Volga Bulgar, which is likey from Proto-Turkic *tog- (“to be born”). Related to dialectal Bashkir and Tatar туган күн (tuğan kün, “Monday; lit. birth day”), Eastern Mari шочмо (šočmo, “Monday; lit. birth day”). Perhaps from Volga Bulgar *طوطوى كوان (tawtuwi küwen).
köken: From Hellenistic Koine Greek Δευτέρα (Deutéra) from δεύτερος (deúteros, “second”) with ellipsis of the feminine noun ἡμέρα (hēméra, “day”): "the second day after Saturday".
Monday (now generally considered the first day of the week in non-religious contexts in Sweden)
çekim: çoğul måndagar · tamlayan måndags
köken: From Old Swedish mānadagher, from Old Norse mánadagr, from Proto-West Germanic *mānini dag, a calque of Latin dies lunae (“day of the moon”), equivalent of måne (“moon”) + dag (“day”). Cognate with Norwegian Bokmål mandag, Norwegian Nynorsk måndag, Danish mandag, Icelandic mánudagur, Faroese mánadagur, Finnish maanantai, English Monday, German Montag and Dutch maandag.