Probably an Arabism.
See also dέlɛ ‘well-bucket; well-rope’ (JL 39).
May eventually be related to the present root with unusual semantic derivations from ‘dark, darkness’ (cf. Bulakh 2006a, 198f.). See also dóhúm ‘heat-haze, shimmer’, edhím ‘to sleep with one’s wife when children or guests are sleeping in the same room’ (JL 36).
dahr- ‘time, period of time; age, duration of life; eternity’ (Lane 923)