The Collaborative International Dictionary of English v.0.48:

Down \Down\, v. t. [imp. & p. p. Downed; p. pr. & vb. n.
   Downing.]
   To cause to go down; to make descend; to put down; to
   overthrow, as in wrestling; hence, to subdue; to bring down.
   [Archaic or Colloq.] "To down proud hearts." --Sir P. Sidney.
   [1913 Webster]

         I remember how you downed Beauclerk and Hamilton, the
         wits, once at our house.                 --Madame
                                                  D'Arblay.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Downing
    n 1: United States landscape architect who designed the grounds
         of the White House and the Capitol Building (1815-1852)
         [syn: Downing, Andrew Jackson Downing]

U.S. Gazetteer Places (2000):

Downing, WI -- U.S. village in Wisconsin
   Population (2000):    257
   Housing Units (2000): 107
   Land area (2000):     2.974642 sq. miles (7.704288 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    2.974642 sq. miles (7.704288 sq. km)
   FIPS code:            20675
   Located within:       Wisconsin (WI), FIPS 55
   Location:             45.046676 N, 92.128496 W
   ZIP Codes (1990):     54734
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Downing, WI
    Downing


U.S. Gazetteer Places (2000):

Downing, MO -- U.S. city in Missouri
   Population (2000):    396
   Housing Units (2000): 210
   Land area (2000):     0.665135 sq. miles (1.722692 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.665135 sq. miles (1.722692 sq. km)
   FIPS code:            19990
   Located within:       Missouri (MO), FIPS 29
   Location:             40.487682 N, 92.368022 W
   ZIP Codes (1990):     63536
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Downing, MO
    Downing