Argued to be a loan from Aramaic שׂוּרָא / ܫܘܪܐ (šūrā), but other cognates such as Sabaean 𐩣𐩬𐩪𐩥𐩧𐩩 (mns¹wrt, “walls”) and Tigre ሶር (sor, “partition wall”) (unless that form is itself borrowed from Arabic) suggest that it may in fact be inherited.
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