The Collaborative International Dictionary of English v.0.48:

battlefield \bat"tle*field\ n.
   a region where a battle is fought.

   Syn: battleground, field of battle, field.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

battlefield
    n 1: a region where a battle is being (or has been) fought;
         "they made a tour of Civil War battlefields" [syn:
         battlefield, battleground, field of battle, field of
         honor, field]

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "battlefield":
   DMZ, aceldama, battle line, battle site, battleground, combat area,
   combat zone, enemy line, field, field of battle, field of blood,
   firing line, front line, killing ground, landing beach, line,
   line of battle, seat of war, shambles, the front, theater,
   theater of operations, theater of war, zone of communications



U.S. Gazetteer Places (2000):

Battlefield, MO -- U.S. city in Missouri
   Population (2000):    2385
   Housing Units (2000): 885
   Land area (2000):     1.983606 sq. miles (5.137516 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    1.983606 sq. miles (5.137516 sq. km)
   FIPS code:            03592
   Located within:       Missouri (MO), FIPS 29
   Location:             37.120151 N, 93.367963 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Battlefield, MO
    Battlefield