The Collaborative International Dictionary of English v.0.48:

nitro \ni"tro\n. [By shortening of nitroglycerin.]
   Nitroglycerin.
   [PJC]

The Collaborative International Dictionary of English v.0.48:

nitro- \ni"tro-\pref.
   1. A combining form or an adjective denoting the presence of
      niter.
      [1913 Webster]

   2. (Chem.) A combining form (used also adjectively)
      designating certain compounds of nitrogen or of its acids;
      as nitrohydrochloric, nitrocalcite; also, designating the
      group or radical NO2, or its compounds, as nitrobenzene
      (C6H5.NO2).
      [1913 Webster]

   Nitro group, the radical NO2; -- called also nitroxyl.
      [1913 Webster]

U.S. Gazetteer Places (2000):

Nitro, WV -- U.S. city in West Virginia
   Population (2000):    6824
   Housing Units (2000): 3217
   Land area (2000):     3.746938 sq. miles (9.704524 sq. km)
   Water area (2000):    0.331375 sq. miles (0.858257 sq. km)
   Total area (2000):    4.078313 sq. miles (10.562781 sq. km)
   FIPS code:            59068
   Located within:       West Virginia (WV), FIPS 54
   Location:             38.415281 N, 81.831249 W
   ZIP Codes (1990):     25143
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Nitro, WV
    Nitro