ZN or Zn may refer to:
Algebra Zn, a cyclic group the ring of integers modulo n in modular arithmetic
Geometry Azimuth, the angle between a reference plane and a point Zenith, the direction pointing directly above a particular location
Science Zinc, symbol Zn, a chemical element Zettanewton (ZN), an SI unit of force Ziehl–Neelsen stain, a bacteriological stain
Other uses Zontanoi Nekroi, a Greek hip hop group Air Bourbon, a French airline (2002–2004; IATA: ZN)