The Collaborative International Dictionary of English v.0.48:

Karroo \Kar*roo"\ (k[.a]r*r[=oo]"), n.; pl. Karroos
   (k[.a]r*r[=oo]z").
   One of the dry table-lands of South Africa, which often rise
   terracelike to considerable elevations. [Also karoo.]
   [1913 Webster]

   The Great Karroo, or The Karroo, a vast plateau, in Cape
      Colony, stretching through five degrees of longitude, at
      an elevation of about 3,000 feet.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "karroo":
   Arabia Deserta, Death Valley, Sahara, barren, barren land, barrens,
   brush, bush, desert, desolation, dust bowl, heath,
   howling wilderness, lunar landscape, lunar waste, outback,
   salt flat, waste, wasteland, weary waste, wild, wilderness,
   wilds