The term<unk>  typically refers to any binary compound of oxygen and<unk> , or to a mixture of such compounds:
Nitric oxide (NO),<unk> (II) oxide<unk>  dioxide (NO2),<unk> (IV) oxide
Nitrous oxide (N2O)
Dinitrogen trioxide (N2O3),<unk> (II, IV) oxide
Dinitrogen tetroxide (N2O4),<unk> (IV) oxide
Dinitrogen pentoxide (N2O5),<unk> (V) oxide
(Note that the last three are unstable.)
Chemical reactions that produce<unk> s often produce several, the proportions depending on the specific reaction and conditions.  This is one reason why secondary production of N2O is undesirable; the other two stable oxides — which are extremely toxic — are liable to be produced.
Nitric oxide, NO<unk>  dioxide, NO2
Nitrous oxide, N2O
Dinitrogen trioxide, N2O3
Dinitrogen tetroxide, N2O4
Dinitrogen pentoxide, N2O5
Nitrogen oxide
Nitrous oxide
Nitrosamine
Sulfur dioxide
Ether
Xylene
Dimethyl sulfide
Acetylene