Wiktionary
nitrene
n. (context organic chemistry English) Any organic compound, the univalent nitrogen equivalent of a carbene, having general formula RN:
Wikipedia
Nitrene
In chemistry, a nitrene (R–N:) is the nitrogen analogue of a carbene. The nitrogen atom has only 5 valence electrons and is therefore considered an electrophile. A nitrene is a reactive intermediate and is involved in many chemical reactions.