The Collaborative International Dictionary of English v.0.48:

Zebra \Ze"bra\, n. [Pg. zebra; cf. Sp. cebra; probably from a
   native African name.] (Zool.)
   Any member of three species of African wild horses remarkable
   for having the body white or yellowish white, and
   conspicuously marked with dark brown or brackish bands.
   [1913 Webster]

   Note: The true or mountain zebra (Equus zebra syn. Asinus
         zebra) is nearly white, and the bands which cover the
         body and legs are glossy black. Its tail has a tuft of
         black hair at the tip. It inhabits the mountains of
         Central and Southern Africa, and is noted for its
         wariness and wildness, as well as for its swiftness.
         The second species (Equus Burchellii syn. Asinus
         Burchellii or Equus quagga), known as Burchell's
         zebra, plains zebra, and dauw, is the most
         abundant, inhabiting the grassy plains of tropical and
         southern Africa, and differing from the preceding in
         not having dark bands on the legs, while those on the
         body are more irregular. It has a long tail, covered
         with long white flowing hair. Grevy's zebra (Equus
         grevyi) is distinct from the others in being placed in
         the subgenus Dolichohippus, whereas the plains and
         mountain zebras are placed in the subgenus Hippotigris.
         More on zebras can be found at:
         http://www.imh.org/imh/bw/zebra.html
         [1913 Webster +PJC]

   Zebra caterpillar, the larva of an American noctuid moth
      (Mamestra picta). It is light yellow, with a broad black
      stripe on the back and one on each side; the lateral
      stripes are crossed with withe lines. It feeds on
      cabbages, beets, clover, and other cultivated plants.

   Zebra opossum, the zebra wolf. See under Wolf.

   Zebra parrakeet, an Australian grass parrakeet, often kept
      as a cage bird. Its upper parts are mostly pale greenish
      yellow, transversely barred with brownish black crescents;
      the under parts, rump, and upper tail coverts, are bright
      green; two central tail feathers and the cheek patches are
      blue. Called also canary parrot, scallop parrot,
      shell parrot, and undulated parrot.

   Zebra poison (Bot.), a poisonous tree (Euphorbia arborea)
      of the Spurge family, found in South Africa. Its milky
      juice is so poisonous that zebras have been killed by
      drinking water in which its branches had been placed, and
      it is also used as an arrow poison. --J. Smith (Dict.
      Econ. Plants).

   Zebra shark. Same as Tiger shark, under Tiger.

   Zebra spider, a hunting spider.

   Zebra swallowtail, a very large North American
      swallow-tailed butterfly (Iphiclides ajax), in which the
      wings are yellow, barred with black; -- called also
      ajax.

   Zebra wolf. See under Wolf.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Equus grevyi
    n 1: zebra with less continuous stripes [syn: grevy's zebra,
         Equus grevyi]