It is hard to say whether this and other Neo-Ethiopian terms for ‘border, limit’ belong to PS *dawr, in view of the semantic difference.
Probably related following Leslau 1956: 247 and EDG 218. See also zəndərä ‘this year’ (EDG 218).
May be related to the present root with a metaphoric shift of meaning (well attesested for this root in Hebrew) rather than borrowed from Cushitic as suggested by Leslau in EDG 204.