Amidogen

Chemical formulae: NH₂, *NH₂,\dot{}NH₂, \dot NH₂, NH₂*

Source: wiktionary

1858, John Joseph Griffin, The Radical Theory in Chemistry, John Joseph Griffin, page 219, According to this theory, azote, in the presence of sufficient radicals, exercises its prerogative of producing amidogens and ammoniums, which then form salts with oxidised carbon, with negative hydrocarbons, or with any other acid radicals, oxidised or not oxidised, which are placed within its reach. But neither amidogens nor ammoniums are produced in the absence of negative radicals with which they can form salts.

Source: wiktionary

1860, John Joseph Griffin, The Chemistry of the Non-metallic Elements and Their Compounds, John Joseph Griffin, page 315, Ammonia is commonly called a base. It is more correct to call it a SALT, and to consider its components to be the radical amidogen NH₂, and the radical hydrogen =\ H.

Source: wiktionary

Again, if in phosgene gas COCl₂, we replace the two atoms of chlorine by peroxide of hydrogen, we obtain carbolic acid; whereas if we replace them by amidogen we get urea, as shown in the second line of the table.

Source: wiktionary