O3 Explained
O3 may refer to:
- O3, the molecular formula for ozone
- , the ozonide anion
- O3, the 1993 debut album by the techno band Sunscreem
- O3 A Trilogy, a 2008 concept album trilogy by progressive metal band Dominici
- O3 star, in stellar classification, a subclass of type O stars
- O-3, the pay grade for the following officer ranks in the U.S. uniformed services:
- Captain in the Army, Marine Corps, Air Force, and Space Force
- Lieutenant in the Navy, Coast Guard, Public Health Service Commissioned Corps, and NOAA Commissioned Officer Corps
- Haplogroup O3 (Y-DNA), a Y-DNA Haplogroup
- Oldershaw O-3, glider
- USS O-3 (SS-64), a 1917 United States O class submarine
- Otoyol 3, a Turkish motorway from Edirne to Istanbul
- Oskarshamn 3, unit 3 at Oskarshamn Nuclear Power Plant in Sweden
- O3 (album), a 2008 album by Son of Dave
- LNER Class O3, a class of British steam locomotives
See also
