The Collaborative International Dictionary of English v.0.48:

greasewood \greasewood\ n.
   A low hardy much-branched spiny shrub (Sarcobatus
   vermiculatus) common in alkaline soils of Western America.

   Syn: black greasewood, Sarcobatus vermiculatus.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

greasewood
    n 1: low hardy much-branched spiny shrub common in alkaline
         soils of western America [syn: greasewood, black
         greasewood, Sarcobatus vermiculatus]

U.S. Gazetteer Places (2000):

Greasewood, AZ -- U.S. Census Designated Place in Arizona
   Population (2000):    581
   Housing Units (2000): 182
   Land area (2000):     5.342960 sq. miles (13.838202 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    5.342960 sq. miles (13.838202 sq. km)
   FIPS code:            29430
   Located within:       Arizona (AZ), FIPS 04
   Location:             35.525467 N, 109.865005 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Greasewood, AZ
    Greasewood