mononitro-Chem.|mɒnəʊˈnaɪtrəʊ|[See mono- 2 and nitro-.]Used to denote organic compounds in which one equivalent of the radical NO2 takes the place of one atom of hydrogen.1869Roscoe Elem.Chem. (1871) 421 Mononitro-naphthalin.1873Fownes' Chem. (ed. 11) 765 Mononitrotoluene.Ibid. 766 The mononitroxylenes are heavy oils.1891Syd. Soc.Lex., Mononitrocellulose, C6H9(NO2)O5, the chief result of the action of cold nitric acid of moderate strength on cotton.