Ereg (Erg)
In Sheltering Sky, Paul Bowles spells it EREG. I finally found it as ERG, which shares a space with erg: a unit of energy. * Anyway, ereg (or erg), from Arabic: a large dune or sand field, having little or no vegetation.
One has just been sent out as a biblical dove, has found nothing green, and slips back into the darkness of the Ark