SO2 or SO<sub>2</sub> may refer to:

Science

  • Sulfur dioxide (SO<sub>2</sub>), a colorless gas with a pungent smell
  • Sulfonyl group (R-SO<sub>2</sub>-R), a functional group found primarily in sulfones, or a substituent
  • SO(2), special orthogonal group of degree 2 in mathematics
  • Oxygen saturation (SO<sub>2</sub>), the concentration of oxygen dissolved in a medium
  • S2 (star) or S0–2, a star near the central black hole at the center of the Milky Way
  • 2015 SO<sub>2</sub> or 2015 SO2, an Aten asteroid

Military and police

  • SO2, a staff officer of the second class, often a commissioned officer of lieutenant commander, major or squadron leader rank
  • SO2, a London Metropolitan Police Specialist Operations command division
  • Special Operations 2 – Operational, of the British, World War II Special Operations Executive

Other uses

<!--* Star Ocean 2, a video game (fails WP:DABACRO)-->

  • SO2 (album), a 2010 album by Shinichi Osawa

See also

  • Oxygen saturation (medicine) (SaO<sub>2</sub>, SvO<sub>2</sub>, StO<sub>2</sub>, SpO<sub>2</sub>)
  • Soso (disambiguation)
  • Soo (disambiguation)
  • SO (disambiguation)