From Old Norse *Sauðar, plural of *sauðr, most likely derived from sjóða (“to boil, seethe”), cf. Swedish dialectal saud m (“spring”) and Low German Sood (“well, pit”). Doublet of Saude, Sauer, Saue, and Saudane. The modern form likely stems from the plural genitive Sauða, as found in compounds like Sauða sókn, akin to Valle < Valla and Molde < Molda.