nitrite

from WordNet (r) 3.0 (2006)

nitrite
    n 1: the radical -NO2 or any compound containing it (such as a
         salt or ester of nitrous acid)

from The Collaborative International Dictionary of English v.0.48

Nitrite \Ni"trite\, n. [Cf. F. nitrite. See {Niter}.] (Chem.)
   A salt or ester of nitrous acid; a compound bearing the
   {-NO2} radical.
   [1913 Webster +PJC]

   {Amyl nitrite}, a yellow oily volatile liquid, used in
      medicine as a depressant and a vaso-dilator. Its
      inhalation produces an instantaneous flushing of the face.
      [1913 Webster]