AMIDOGEN
Etymology
Noun
amidogen (plural amidogens)
(inorganic compound, dated) The amino radical, •NH2, the neutral form of the amide ion −NH2−, regardable as the ammonia molecule with one of its hydrogen atoms removed.
Synonyms: amido group, amido radical, amino radical, aminyl radical, azanyl radical, dihydridonitrogen.
Source: Wiktionary
A*mid"o*gen, n. Etym: [Amide + -gen.] (Chem.)
Definition: A compound radical, NH2, not yet obtained in a separate state,
which may be regarded as ammonia from the molecule of which one of
its hydrogen atoms has been removed; -- called also the amido group,
and in composition represented by the form amido.
Source: Webster’s Unabridged Dictionary 1913 Edition