For Nabataean (RES 471=Cantineau p. 21)
ˀrktˀ see s.v.
ˀrṣh n.f. ; but Healey
The Religion of the Nabataeans p. 144 rejects the interpretation 'sarcophagus' on the grounds that such a thing could not be dedicated to a god and suggests 'portico(?)'; but perhaps simply 'long stone'.