資料來源 : Webster's Revised Unabridged Dictionary (1913)

Nitro- \Ni"tro-\
   1. A combining form or an adjective denoting the presence of
      niter.

   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.

   {Nitro group}, the radical {NO2}; -- called also {nitroxyl}.

資料來源 : WordNet®

nitro group
     n : the group -NO3